At breakfast one morning in October, she said, “We should go for a ride. Maybe even go away for the weekend in the sidecar.” My mind filled with options, plans, routes and ideas. We talked about it for 15 minutes before she had to leave for work, and I resolved to move my rig out from under the tree where it slumbered all summer, go put some fresh gas in it, and get it ready for a weekend jaunt.

Imagine my surprise and dismay when, at the stop sign at the end of my street, I discovered my front brakes were completely non-functional. Gone. One hundred percent useless. Luckily, I live in a rural neighborhood, so nobody cared (or hit me) when I blew past the stop sign while relying solely on the rear brake to halt my forward progress.

Disappointment was the word of the day, but we’re both glad I discovered the defect before hitting the highway. When I got safely back to my driveway, I scolded myself for not doing TCLOCKS or SCMODS or whatever it’s called when you give your bike the once-over before riding off. You can go ahead and scold me for it, too, but I have a bad habit--as I suspect many of you do as well—of just getting on the bike, starting the engine and riding off. Lesson learned.

Back in the driveway, in the harsh light of day and without the covers on the rig, I could clearly see the telltale signs of leaked brake fluid on the right side panel. Not just a few drops, either, but a lot of it. Just to be sure, I took the cover off the master cylinder and sure enough, there wasn’t any brake fluid left in there at all. I pumped the lever a few times and…nothing. Dollar signs flashed before my eyes as I wondered what a new master cylinder would cost (p/n 32 72 7 650 773, $536.89), and I shed a single tear at the prospect of all that brake fluid ruining my beautiful paint.

First things first, though. A call to the number on the back of my MOA Membership Card triggered my Roadside Assistance plan, and I remain grateful for the 100-mile towing aspect of the MOA’s Roadside Assistance program. After the 87-mile tow to the shop—which, by the way, we have renamed from Beemers Uber Alles to Gridlock Motors for a variety of reasons—my boss, George Mangicaro, seemed nonplussed. “Yeah, this happens,” he said. “How long was the bike sitting?”

Shamefully, “I don’t know” was all I could answer.

“When’s the last time you flushed the brake fluid?” was his follow-up question.

I couldn’t even make eye contact with him at that point. It’s that old adage about seeing doctors smoking at a hospital: we always tend to take better care of our clients, customers or patients than we do of ourselves. I would never let a customer leave the shop without reminding them to “have that brake fluid flushed in a year!” but apparently, I don’t follow my own advice. Looking back through my maintenance log, I discovered the last time the brake fluid got flushed my 1998 K 1200 RS was in April 2015, when George modified the bike so I could use the handlebars from a K 1200 GT to get a little more steering leverage for the heavy rig. I didn’t need to look at a calendar to know I’d blown past even BMW’s recommended brake fluid service interval of two years by a year and a half.

It was no surprise to discover that the reason my brake fluid leaked out was because the rubber rotted out of my master cylinder. My apologies for the wretched photo, but even in a blurry photo you can see the damage done internally by the old, crusty brake fluid.

Corrosion from old, contaminated brake fluid degrades internal components of master cylinders over time and can damage or destroy other components as well.

Lucky for me, we’d taken in a number of parts bikes in the last year before moving the shop, so we happened to have a clean used master cylinder in a bin. (Luckier for me, George organized everything from the old shop before he moved, so he knew exactly which bin to look in to find it!) In just a couple of hours, my rig had functional front brakes again, and I’ve learned an important lesson all over again.

You see, this isn’t my first battle with motorcycle neglect. You may remember a column not long ago in which I encouraged all of you to avoid using cheap parts. I was specifically referring to the KTM shop that put low-pressure fuel lines on my fuel-injected 2007 990 Adventure, something that ended with me stranded on the side of the road due to a burst fuel line. The reason the shop put those low-pressure fuel lines on in the first place was because that bike had been seriously neglected; its previous owner, a friend of mine who unfortunately passed away not long after we made the deal, left that poor KTM outside in Iowa under a cover for about two and half years. When I got the bike home, I quickly discovered a dozen or more things needing attention to deal with rot, cracking, rust and more.

That lesson didn’t even sink in fully, which is why my poor K 12 RS sidecar rig suffered such an ignominious fate. Fortunately, you can learn from my mistake and make it one of your New Year’s Resolutions not to neglect your motorcycle(s). You can achieve that goal (and make a habit of it) by using some of these pointers.

• Flush your brake fluid once a year, front and rear, and include the ABS unit if your bike is so equipped. Be sure to check what type of fluid (DOT 3 or 4 are most common for BMW motorcycles) your bike needs and have plenty of it on hand. Discard unused brake fluid after a couple months of sitting, even in a tightly sealed container; brake fluid is hygroscopic (it absorbs water from the atmosphere), which is why it breaks down over time.
• If your clutch uses brake fluid, flush that once a year as well. If it uses mineral oil (check your owner’s manual to be sure), that doesn’t need flushed as often, as it shouldn’t absorb water from the atmosphere like brake fluid does. Still, it’s not a bad idea to flush it every other year to keep your slave cylinder functioning smoothly.
• Check all exposed rubber—hoses, covers, tires, etc.—for obvious cracks. Heat cycles (cold-hot-cold) and UV exposure degrade rubber over time. Tires with cracked sidewalls should be replaced, and any hoses with cracks should likewise be replaced as soon as possible.
• If your motorcycle is water cooled, flush that system once every two years at the least. Contaminated coolant can quickly become corrosive, which could damage a lot of important stuff on your motorcycle. It’s not a bad idea when the system is empty to pull the water pump and inspect it closely. On some older K bikes especially, the water pump is a known weak point and often needs rebuilding following an inconvenient failure, usually when you’re hours and hours from the nearest dealership.

My resolution is to flush these systems once a year on all my motorcycles, regardless of how many miles I’m putting on the bike. I’m going to extend this resolution to the other oils on the bike—engine, transmission and final drive. At least once a year, no matter the mileage. One of the reasons I let the maintenance go on my sidecar rig is simply because I don’t ride it often. Hopefully that will change in 2019, so please don’t laugh too hard if you see a beautiful blue K 1200 RS with a sidecar with one ugly, stained side panel.

Once the broken components came off and the new, gently used ones went on, the brakes not only worked again, but everything looked good, too.

When Henry Ford rolled out the Model T in 1908, it put 20 horsepower to the ground with a 179 cubic inch inline-four engine. The Model T had a top speed of about 40 miles per hour and got about 18 miles per gallon. The fuel of choice for that first Model T was ethanol, which 1908 America's legions of farmers could make at home in quantities great enough to both fill the T's 10-gallon fuel tank and make moonshine. Ethyl alcohol, the substance we call ethanol, quickly fell out of favor as a fuel for internal combustion engines simply due to the increasing use and rapidly declining price of gasoline. Ethanol is easy to make in about a week and only requires corn, water, yeast, sugar, heat and patience.

Despite losing favor as a single-substance fuel source, ethanol got into the gas tank again in the 1920s, when Standard Oil started adding it to their gas to boost octane in an attempt to reduce knocking in engines. With the Great Depression in full swing in the 1930s, Americans bought "gasohol," a 90/10 gasoline/ethanol mixture. Gasohol enjoyed a brief comeback during World War Two, when most U.S. manufacturing and production went to the war effort. Following the end of the war, however, ethanol disappeared from the gas supply in the U.S. as the nation enjoyed unprecedented industrial success and economic growth.

The oil crisis of the 1970s brought ethanol into vogue yet again, and Congress created incentives and subsidies for companies researching the conversion of organic material, like corn, into energy. First up was the Solar Energy Research, Development and Demonstration Act of 1974, and the Environmental Protection Agency (EPA) got in on the game by kicking off a 13-year phaseout of lead in gasoline. Ethanol found its way into nearly every gallon of gas sold in the U.S. during that time as an anti-knock additive, suddenly important due to the missing benefits of having lead in the mixture.

In 1978, the Energy Tax Act reintroduced the term gasohol, defining it as a substance with at least a 90/10 gasoline/ethanol blend. This law effectively created a $0.40 per gallon subsidy for ethanol producers, spurring production of the volatile liquid in 10 distillation facilities that eventually produced upwards of 50 million gallons of ethanol every year. In just under a year, Amoco, Chevron (formerly Standard Oil), Texaco and other major refiners were pumping millions of gallons of ethanol-blended gasoline into American fuel tanks.

Congress boosted its support of ethanol production throughout the 1980s, starting with the Energy Security Act in 1980 that guaranteed a million dollars in loans for any firm willing to put up 90 percent of the construction cost for an ethanol plant. That same year saw barriers go up against importing foreign ethanol. By 1984, there were over 160 ethanol plants in the U.S., and the government bankrolled $0.60 of every gallon of ethanol produced in the country. Even this massive subsidy wasn't enough; by the end of 1985, about half of the ethanol plants had gone bust. Ethanol subsidies didn't drop below $0.50/gallon until 2011, when Congress removed completely the $0.45/gallon ethanol subsidy effective 1 January 2012. That had the effect of raising gas prices a little over four cents a gallon almost immediately.

The idea of using a 90/10 gasoline/ethanol blend in winter to control carbon monoxide emissions got its official start in Colorado in 1988. In 1992, amendments to the Clean Air Act mandated the wintertime use of ethanol in gas in 39 urban regions in the U.S.—regions where the EPA said the emissions danger to the ozone layer was the highest. A dozen states boosted their subsidies in the mid-1990s due to poor corn harvests (which drove corn prices higher), which caused ethanol producers' material costs to skyrocket despite most of them switching from coal to natural gas for their power source.

In the late 1980s the refining industry started putting methyl tertiary butyl ether (MTBE) in our gasoline. MTBE is made by fusing together natural gas and petroleum. Unfortunately, by the end of the 20th century, scientists and environmentalists found enough MTBE in America's water supply for the states, and eventually the federal government, to start banning its use, a process completed in 2003. MTBE was replaced by ethyl tertiary butyl ether (ETBE), a substance made by fusing together (wait for it!) ethanol and petroleum, further increasing the percentage of ethanol pushed into every gallon of gas. However, the amount of ETBE in a gallon of gas isn't included in the measurement of how much ethanol is in a gallon of gas, because ETBE is considered an additive instead of one of the base ingredients; this means that your E10 gasoline at the pump isn't really E10 gasoline.

Congress ensured the perpetual presence of ethanol in America's gasoline supply by passing the Energy Independence and Security Act of 2007, legislation that ordered 36 billion gallons of ethanol and other substances be blended into the fuel supply by 2022. According to the Renewable Fuels Association, a pro-ethanol organization, the now 200-plus ethanol refineries in the United States are currently capable of producing over 16 million gallons of ethanol per year.

Ethanol is considered a green fuel because it comes from a renewable resource—corn. However, every ear of corn that gets mashed to make ethanol is an ear of corn that doesn't get processed into cattle feed, corn meal, high fructose corn syrup or tortillas. It's touted by the ethanol production industry as "clean burning," "high octane" and a "job creator." Speaking out against its use is therefore tantamount to political suicide for any public office holder willing to take on this issue, especially in the corn-producing states of the American Midwest. Any individual citizen that decries the use of ethanol runs the risk of being branded as unpatriotic, even if they're only concerned about the health and well-being of their vintage motorcycle's fueling system.

The damage alcohol does to the human body is well documented. We consume ethyl alcohol (ethanol) in massive quantities as a society, legally, straight from the bottle, can or box. When consumed, ethanol receives front-of-the-line service inside our bodies, getting processed ahead of nearly everything else we might consume at the same time. Alcohol's processing starts in the stomach, where the dehydrogenase enzyme starts to break it down; most of the alcohol is absorbed in the small intestine, but about a tenth of it goes out through exhalation, perspiration and urination; this is why you can literally smell alcohol on somebody's breath. From the small intestine, blood carries alcohol to the liver, where it is attacked as a poison. The liver works desperately to clean it out of the blood and return the body to equilibrium, which is why chronic alcohol abusers often suffer liver failure. Their liver simply wears out from processing so much alcohol.

In addition to the damage this substance does to our society through the scourges of alcoholism and drunk driving, it can also contribute to a myriad of health problems such as cancer, heart disease, obesity, hyper- and hypoglycemia, kidney disease, liver disease and other syndromes. The current blend of about 10 percent ethanol in each gallon of gas, while perhaps not totally ideal, is easily processed by modern internal combustion engines, from tiny thumpers in weed eaters to massive V-12 behemoths in supercars. This mixture, referred to as E10, has been in more or less continuous use for two generations. As long as it's not stored for long periods of time, it doesn't attract too much water, gum up too many fuel systems or damage too many vehicle components. For most car drivers, this isn't too much of a problem; as Americans, we're a car culture, and we drive a lot, burning up about 400 million gallons of gasoline every single day.

As motorcyclists however, the cycle of storing and riding requires careful attention. While pure gas—or "E0" as refiners refer to it—can go "stale," lose its volatility and gum up the works in our carburetors or fuel injection systems, the introduction of ethanol into the gasoline both accelerates and exacerbates this process, causing more problems and damage and doing it more quickly, even with "just" E10. This is the main reason it's important to add a fuel stabilizer to the fuel system of a motorcycle being stored with a gas in the tank for any extended period of time (i.e. more than three months). The stabilizer prevents the staleness and helps keep the ethanol from absorbing water and coming out of solution.

It's 2019 and the world is changing. Where I live in central Virginia, we've had the hottest and wettest summers in recent years, beating records dating back to 1936, continuing an upward temperature swing that's trending up since 1900 and accelerating since 2000. One of the results of that ongoing trend has manifested recently in a terrible drought parching more than half the nation. In 2000, corn cost about $110 per metric ton (2,205 lbs.), or about $2.82 per bushel (56 lbs.). In 2008, corn prices spiked to $293/mt ($7.50/bushel), dropping to about $150/mt ($3.84/bushel) in 2009; due to the drought, however, corn spiked to just over $338/mt ($8.66/bushel). The drought is not predicted to get better any time soon and may, in fact, extend over the next decade, driving corn and other food prices up for possibly the next 25 years.

One bushel of corn, processed properly, results in two and a half gallons of ethanol. That's enough to manufacture 25 gallons of E10 fuel. Unfortunately, only the more difficult—and thus more costly—wet-milling method of processing corn yields ethanol. It may cheer you to know that wet-milling for ethanol production creates useful byproducts, such as 12 pounds of cattle feed, three pounds of corn meal, a pound and a half of corn oil and 17 pounds of carbon dioxide, generally captured to use as an industrial refrigerant or to fizz up carbonated beverages, per gallon of ethanol. (Processing and output data from North Dakota State University.) Even before factoring in the transportation, processing and storage costs involved in diluting gasoline with ethanol, eliminating ethanol from our fuel supply could create an immediate drop in the cost of gasoline, not to mention an immediate improvement in the quality of gas and a relaxation of strain on our food supply. Such disparate groups as the U.S. Department of Agriculture and the International Food Policy Research Group agree, both issuing reports in August 2012 that point to a causal relationship between the ongoing drought and high (and rising) corn prices.

Removing, even temporarily, the ethanol requirements for gasoline could bring down both corn and gasoline prices. In the Obama administration, the EPA held fast to its position that ethanol reduces the amount of pollutants spewed by internal combustion engines, refusing to agree to even a temporary waiver of the ethanol requirements. The Trump administration refuses to alter the ethanol requirements for other reasons.

In fact, in 2011, the EPA authorized the sale of E15 gas, fuel with 15 percent ethanol in it. While they said it should only be used in cars and light trucks made from 2001 on, opening that door allowed the corn and oil industries to charge right on through it. Federal law prohibits the use of E15 in any gas-powered tool or vehicle other than a car or light truck and the EPA acknowledges that E15 will damage these engines. The real risk is the use of blending pumps, which allow dispensing of E10, E15, E30 and E85 fuels based on the customer's choice. Using those pumps can and will destroy motorcycle engines. Even California, with its reputation of existing on the cutting edge of emissions-reducing legislation, refuses to approve the sale or use of E15 within its borders, which should tell us a lot of what we need to know about the substance.

There may never be a day when our gasoline is free from ethanol, but perhaps we can see an end to the calls to increase the percentage of each gallon of gas that is given over to ethanol. Maybe the popularity of television series like Boardwalk Empire and Moonshiners will help in that arena, as it's boosted the demand for moonshine – or at least the legal versions of corn whiskey. Corn, after all, belongs in our bellies, not in our gas tanks. Come back next month when we take on octane, which is far more misunderstood than how much ethanol goes in your fuel tank.

The MOA avoids political discourse as a matter of policy, and neither the MOA nor its Board of Directors endorses the author's request that all motorcyclists engage with their duly elected senators and representatives at both the state and federal levels to encourage them to stand up for less ethanol in our gasoline. The rise of E15 is of particular concern to motorcyclists, as that foul substance stands to contribute significantly to the early demise of the powerplants of our beloved conveyances.

Data and statistics gathered from fuel-testers.com, gpreinc.com, ifpri.org and upi.com. Search pure-gas.org to find ethanol-free gasoline near you in the USA and Canada.

When I got to the tech specs of the new bikes, I noticed something and thought, “Hey, I’m a pretty tech-aware guy, and if this confuses me, maybe there are other people who wonder about this as well.” I am referring to the part of the specs where BMW recommends what kind of gasoline should be used for the bike. In this instance (and you can refer back page 69 of the January issue to see what I’m talking about) the F 750 GS spec is for 91 RON gas, while the F 850 GS is rated for 95 RON fuel. The spec sheet calls 91 RON “regular” and 95 RON “premium,” but most of us reading this magazine don’t see 91 next to “regular” on the gas pumps we use.

Perhaps the confusion stems in part from not knowing that when you read the tech specs for a BMW motorcycle, BMW is referring to the sticker on the pump in Germany. The good news is that at its most basic level, regular gas is regular gas, and 91 RON in Germany is equivalent to 87 AKI in the United States. Premium is the same, and while premium gasoline is often called “super” by some retailers, 95 RON in Germany is equivalent to 91 AKI in the USA and Canada. What they call “super plus” in Germany in 98 RON, or 93 AKI stateside.

You can stop reading right there and take away a couple of things. First is the knowledge that regular means regular and premium means premium (or super), and if that’s all you remember when it comes to your motorcycle, you’re fine. The second is nobody really bothers specifying those mid-grade fuels, so in general you can just skip them unless they’re your only choice for some reason.

On U.S. and Canadian pumps, you’re generally presented with three choices: 87, 89 and 93. Some stations throw in 88, 91 or even 95. We think of gasoline as the go juice for our motorcycles, but there’s more to it than just suck, squish, boom, blow, especially when it comes to the amazing technology built into our modern motorcycles. In the old days when one twist grip was the throttle and the other advanced the timing, the rider had to have a feel for what was going on with the bike at all times. Fuel injection and computers have taken that need from us, thankfully, but that doesn’t mean we can’t understand what’s going on.

The abbreviations we see used to describe the quality of gasoline are varied, but luckily there are only a few of them.

• RON: Research Octane Number, used in Europe and most other places in the world
• MON: Motor Octane Number, usually accompanies RON
• AKI: Anti-Knock Index, used in Brazil, Canada, the U.S. and a few other countries
• RdON: Observed Road Octane Number, not seen on pumps

The RON of a particular blend of gasoline is determined by scientists and engineers who run the gas through a test engine at 600 RPM under tightly controlled conditions. The engine itself is special, because unlike your motorcycle, the compression ratio of the engine can be altered on the fly. MON is determined at 900 RPM using fuel that’s been warmed up, and the special engines used for MON testing have variable ignition timing on them.

AKI isn’t determined by testing, but rather by mathematics. You take the RON, add the MON to it, then divide the sum by two. You may recognize the formula (R + M)/2 as what we commonly refer to as an average, and you’d be right. Where MON is usually 8 to 12 numbers below RON, AKI is usually 4 to 6 numbers below RON, right about in the middle between MON and RON.

The K in AKI stands for Knock, and you don’t want your engine to knock. When an engine knocks, that means the air-fuel mixture in the cylinders is burning unevenly or incompletely, neither of which is good for your engine. While there are other things that can cause knocking, such as worn out spark plugs or excessive carbon deposits in the cylinders, we’re talking about octane here, so that’s what we’re going to focus on. (Maintenance note: if two or three tanks of the proper AKI-rated gasoline don’t eliminate your engine knocking problems, put in new spark plugs.)

Knock sensor illustration from AZO Sensors.

Here’s the important part: gasoline with a higher AKI (or RON or MON) can withstand more compression at a given temperature before it ignites. High performance engines with high compression require high AKI gasoline, it’s that simple. You might save a little money by putting 87 in your engine that requires 91, but over time you’re not doing yourself any favors by introducing increased wear and poorer performance to your motorcycle engine.

At the gas station closest to my house (at the time of this writing (mid-December 2018), 87 AKI gas costs $1.99 per gallon and 93 AKI costs $2.89 per gallon, a difference of 90 cents a gallon. My 2005 R 1200 GS holds 5.3 gallons of fuel, so filling a completely dry tank would cost me $10.55 with 87 and $15.32 with 93. Filling my tank with 93 therefore costs me $4.77 over filling it with 87.

The compression ratio of my engine is 11.0:1, and BMW specifies the use of 95 RON gasoline – 91 AKI. Since my nearest gas station doesn’t sell 91, it’s better to go over (93) than under (89). Having said that, one of the great things about the GS platform is that BMW intends them to be ridden anywhere at any time, and incorporates whiz-bang computer programming called Automatic Knock Control to enable cheapskates all over the world to use 91 RON (87 AKI) gasoline.

Automatic knock control is typical for automotive engine management systems, and it’s becoming increasingly pervasive in motorcycles. Its function is simple: when the sensors detect knocking, the bike’s computers delay the introduction of the spark into the cylinder. This gives the piston an extra split second to compress the fuel-air mixture to the correct level. Due to the process of four-stroke internal combustion, this means that the piston is likely on its down stroke when the knock-retarded ignition takes place. This robs you, the rider, of power and decreases fuel efficiency over time.

One of the problems with engine knock is that by the time you actually hear it, the damage is done. Engine knock sounds occur around 6-8 kHz, which is in the middle of humans’ hearing range, but they’re not typically loud sounds until you really have a problem. You’re more likely to feel knocking through your butt, hands and feet before you hear it. Once it gets bad enough to be audible, you could be looking at serious engine problems.

The way to prevent knock, then, is to use fuel with an appropriate octane rating for the compression ratio of the cylinders. This comes down to math yet again, but it’s easy math if you have the data. Find out the volume of the cylinder with the piston at bottom dead center and compare that to the volume of the cylinder with the piston at top dead center; the resulting ratio represents what kind of gas you need to run in your bike for peak performance. An engine with a high compression ratio, as is the case with the above-mentioned F 850 GS, requires higher octane gasoline than an engine with a low compression ratio.

Determining the volume is a little more complicated, math-wise. You have to know the bore and stroke of the cylinder, the compression height of the piston as well as its dome height (or dish depth), the piston-to-deck clearance (bore squared x 0.7854 x distance between piston and deck at TDC), and even the thickness and bore of the head gasket. Then and only then can you run the formula through to determine the compression ratio. This is perhaps why we take the manufacturer’s word for it when it comes to compression ratios.

Here’s where the monkey gets the wrench, though. Because of any number of myths and a certain level of ignorance as to how gasoline and internal-combustion engines function, many riders believe that putting premium gas into an engine with a low compression ratio will boost performance. It simply will not. Premium gas is not better gas than regular gas, it simply has higher octane to be suited for engines with a high compression ratio. As far as your low-compression-ratio-engine is concerned, the excess octane beyond what it requires is wasted, which means the extra 30 cents a gallon you spent on that 93-octane fuel when your bike only needs 87 became dust in the wind. Unless, of course, your engine is pinging and knocking. In that case, try buying a couple tanks of gas one octane rating higher than usual and see if that takes care of the noise. If it does, it’s time for a tune-up, because something is out of spec with your engine. If going up one grade of gasoline doesn’t work (or isn’t possible), you may need to consult a qualified motorcycle mechanic.

In the end, Super and Premium are words used by marketing experts to trick you into buying gas you think is better for your car or motorcycle rather than Regular or Mid-Grade. After all, you’re special, so your motorcycle must be special too, right? Problem is, unless you’ve got an absolute ton of money, your bike isn’t special. Certainly your 2007 R 1200 RT isn’t special, and there isn’t a gallon of 98 octane fuel anywhere in the world that’s going to improve the performance curve of your bike.

Read Part Two of this series on fuel and fueling at C2H2OH: Ethanol.

My grandfather was a hard man, and blunt to boot. He served in the army during World War II, Korea, and in the Ohio National Guard for decades. He was a police officer for many years, as well. A child of the Great Depression, he didn't trust banks and indulged in creature comforts like a good cigar or a big, comfortable four-door sedan. Not long after I graduated from high school, I asked him for advice about a difficult situation I had gotten myself into. "Don't be stupid," he said. "Everything is harder when you're stupid." At 18 years old, I didn't quite understand the depth of such simple advice, but as an adult I have come to rely on it more and more often.

Except, it seems, when it comes to my motorcycles.

Regular readers of my tech exploits will remember that many moons ago, a lengthy maintenance cycle presented me with an easy opportunity to detach the starter from the transmission of my 2005 R 1200 GS and measure the thickness of the clutch components. With nearly 80,000 miles on the bike, this should have been a no-brainer, yet I squandered the opportunity. Sure enough, 3,000 miles later my clutch failed. Had I spent 15 extra minutes at 80,000 miles, I could have saved myself months of waiting and hours of work.

During the clutch replacement, I had the opportunity to take care of a mundane task that, because I didn't think about it at the time, went on to strand me at a gas station and require me to fetch a trailer to retrieve my bike. My grandfather's words came back to me as I stood next to my bike in the driveway, fruitlessly trying to get it to start.

The symptoms were simple: with ignition on, kill switch set to "go" and the starter thumbed,. the result was no clicks, no whirrs, no feeble attempt to turn over at all. There was also no bright green N telling me the bike's transmission was in neutral and no zero in the gear indicator box to confirm Mr. N's glow.

My bike refusing to start in anything other than neutral had been an ongoing issue since mid-2015, but one I worked around by simply starting my bike in neutral. There's two things that could cause that particular problem: a bad kickstand switch or a bad (or out of adjustment) clutch switch. I had reason to test my kickstand switch not long ago and found it to be good, so my assumption was that the clutch switch needed adjusted or replaced. I was wrong about that, but it turned out not to be my fault. The aftermarket brake and clutch levers I installed on my bike in mid-2015 are adjustable, and unless they are adjusted to one of the extremes possible, they simply don't engage the clutch switch properly. This was communicated to me by the folks at Adventure Designs, from whom I bought the JPR "shorty" adjustable aluminum levers. I don't remember this feature being part of the hardware documentation, but then again, I don't remember reading any hardware documentation.

With the kickstand and clutch switches now out of contention as the cause of the problem, I turned to the thing that tells me and the motorcycle's computer that the transmission is in neutral. This electronic device is called a gear indicator potentiometer, and it's bolted onto the back of the transmission.

You've probably been waiting for the stupid part to come back around. Gentle reader, I am nothing if not here to prevent your ongoing disappointment, so here it is. Ever since I got this motorcycle in 2010, it has done this weird thing. If I stay in fifth gear too long, the gear indicator on my dash would change from 5 to 6, then go blank a few seconds later. It would stay blank for some indeterminate period of time, occasionally flashing a random gear number, then seemingly resetting itself to normal operation. As time has gone on, the amount of time in fifth gear to cause this fault has gotten shorter, and the amount of time for the bike to reset itself has gotten longer.

This issue was not forgotten during my clutch replacement, but a new gear indicator potentiometer costs $220, and I was already into my bike for over $1,400 on that clutch. I just couldn't bear to add another two bills and change to the parts bill. I didn't even pull it out to check or clean it. As my grandfather would say, stupid. The only way to confirm my diagnosis that the shift indicator potentiometer has finally gone the rest of the way bad is to hook the bike up to a diagnostic tool and read the fault codes. I could have gone to a dealer and had them hook it up to an official BMW computer, but queues are long, and I'm not one to demand special front-of-the-line treatment from people I didn't buy my motorcycle from (or anybody else, for that matter). Instead, I went to Beemers Uber Alles, where I work in an increasingly sporadic fashion, and hooked my bike up to our GS-911 diagnostic interface.

After the system scan, attention-grabbing red letters told me what I already knew: "10115 Gear position potentiometer. The fault is currently present." I clicked the button to clear the fault codes from the bike's computer.

A flash of green caught the corner of my eye and I heard the fuel pump prime. The realization that I just fixed my motorcycle WITH A COMPUTER struck me like Wile E. Coyote running full speed into a wall painted to look like a road tunnel.

No wrenches. No Torx drivers. No sockets. A computer. My mind went immediately to 2001: A Space Odyssey and Hal refusing to open the pod bay doors for Dave.

After subjecting my motorcycle to another ignominious two-hour trip on a trailer, I sent Ted Porter (of the Beemer Shop) an email. "Thank you, Ted," I wrote. "You saved my sanity today. Thanks to the GS-911, not only did I confirm what's wrong with my motorcycle, but I was able to get it to start again by clearing the fault codes." The Beemer Shop isn't the only place you can buy a GS-911, but Ted was the first to import it into the USA, and the knowledge he and his staff possess of how the device and its accompanying software works is dizzying. He explained to me the differences between the Enthusiast and the Professional licenses. Ted stressed that even if the Enthusiast license holder has maxed out the allowed 10 VINs, that GS-911 can still be used with a mobile device (Android or iOS) to read the codes on any compatible BMW motorcycle and more importantly, reset the fault codes. Had I been stranded somewhere on the road instead of stuck safely at a gas station and then in my own driveway, this functionality would have been critical to saving my day and getting me back on the road.

Buying a GS-911 is probably only suitable for the more hardcore, "I do my own maintenance" riders out there, and on top of that, only the ones willing to shell out for its not insignificant cost. A GS-911 is not a substitute for the knowledge and experience brought to motorcycle repair by a qualified, educated BMW motorcycle technician, but it can definitely save an otherwise ruined ride and give consumers a good place to start when discussing their maintenance and repair needs with their chosen qualified professional mechanic.

While I've used one in the shop for several years, I'm now of the opinion that having a GS-911 in my tool kit is as important as having my other go-to bit of electronic wizardry, a digital volt-ohm meter (DVOM). A GS-911 and its accompanying mobile app could get me back on the road, and I'm sure it will allow me to help other riders I encounter in my journeys. I'll discuss DVOMs in depth in a future column and also look at how to replace the gear indicator potentiometer. I might even dissect the broken one to see its innards and maybe figure out why it malfunctioned.

You can learn more about the GS-911 from the manufacturer's website, hexcode.co.za, and you can buy your own from Ted Porter's Beemer Shop and other online retailers. Prices start at $299.

BEFORE YOU PUT IT IN STORAGE

(1) Wash your bike thoroughly, by hand, with a soft rag and appropriate soapy water. Don't use dish soap if you can help it, but if that's all you have, be sure to dilute it with plenty of water. Be methodical – start at one end of the bike and work your way patiently to the other end.

This is less a way to achieve a clean bike and more a way to put your hands and eyes on every visible component of the motorcycle for a hard check. You'll notice a loose bolt or a missing nut. You'll see if your tires need replaced. You'll be able to determine if this component or that one needs attention or tightening. It's the easiest and one of the best ways to build confidence in your motorcycle as well as your understanding of the interconnectedness of the motorcycle's subsystems. Adjust or repair anything you come across that needs attention.

If you motorcycle is chain driven, the washing process should also include a thorough clean and lubricate cycle for your drive chain, though you may want to save chain cleaning, adjustment and lubrication until after you've finished the other storage prep steps below.

This is a good time to check the condition of your brake rotors and pads, brake lines, coolant and fuel hoses, etc., and either repair or replace them before you store the motorcycle or make a note to have them taken care of as soon as the riding season starts.

(2) Change the oils (engine, transmission, final drive) and engine oil filter. When it comes to motorcycle operation, oil has three primary operations: Lubrication, cooling and cleaning. Lubrication and cooling are the two most of us think about when we think about oil, but it's important to note that oil will also store (by suspending in solution) both chemical and metal contaminants it picks up from inside the engine, transmission or final drive.

Changing the oils before you store your motorcycle gets these contaminants out of there so they're not sitting in the engine, transmission or final drive while the bike is in storage. Depending on the make and model of your bike, this step could cost you a hundred or so dollars. I realize due to the cost that some riders will skip it, but it's an important step in preserving the life of your bike.

(3) Fill the fuel tank with fresh, high-quality fuel. This is especially critical if you have a metal fuel tank. By filling up your (metal) tank all the way, you minimize the surface area of metal that is exposed to air, which means you reduce the likelihood of rust getting a foothold inside the tank. Once rust gets started, it's hard to stop and you could be in for a costly relining of your tank. Plastic tanks obviously do not rust, but many fuel tanks have metal components inside them – fuel line clamps and fittings, fuel pumps, etc. – and so filling them all the way up is cheap insurance against any kind of rust or corrosion getting started.

Use ethanol-free gasoline if you can, but it's not critical for short term storage (up to about three months). You can find a station that sells ethanol-free gas (hopefully near you) by using the website pure-gas.org.

(4) Add stabilizer to the fuel. This substance comes in many brand names, but the purpose is pretty much the same no matter what brand you get. Fuel stabilizer serves to keep gasoline's volatile compounds intact, primarily by keeping ethanol in solution. When ethanol separates, it attracts water, and that water will sink to the bottom of your tank (because science: water is heavier than gasoline). Not only can that water sitting at the bottom of the tank promote the development of rust (just ask any K 75 S owner), but it could get sucked into the fuel intake at an inopportune moment and shut down your engine.

I use Sta-bil for storage and in my lawn mower and other gasoline-powered devices, but there are a number of brands on the market that work just like Sta-bil. Find one you like and use it. If you're not sure which one to use, ask anybody you know that owns a boat and try what they recommend. Boats often sit for months at a time and part of routine maintenance for many boat owners is using fuel stabilizer, so they're likely well equipped to offer advice in that regard.

(5) Inflate the tires to the manufacturer's recommended specification. While the tires are likely to lose some air during storage, it's always good to set a known baseline.

WHILE IT'S IN STORAGE

(6) Hook your battery up to a charger/tender. There are dozens of these on the market, so choosing one can be a mind-boggling experience. I use an Optimate 4 Dual Program because most of the year, my bikes sit outside and the O4DP is sealed, so it's OK if it's out in the rain. The O4DP is also a good choice because it's rated for any kind of battery you might have in your bike, whether it's a lead-acid battery (wet/flooded, AGM or gel) or a lithium-iron (often misstated as lithium-ion) battery. Don't throw out the instructions, and use as recommended. (Read a lengthy article about the differences between AGM and lithium-iron batteries.)

Another reason I like the O4DP is because, unlike a straight battery charger, you can leave the O4DP connected to your bike for an extended period of time without damaging the battery. It's a smart enough device not to pummel your battery with a constant, steady stream of high-powered electrons. It will charge your battery up to its proper level, then maintain it so it's ready to go when you are. Just make sure the outlet it's plugged into is protected from precipitation.

Note the Sta-bil in the upper left corner. If you can, keep your charger/tender's cables off the ground. This will help keep critters from chewing on them.

If you're not going to hook your battery up to a charger/tender, then disconnect the wires to the battery and, if it's a flooded (wet) lead-acid battery, remove it from the motorcycle to prevent any possible problems related to weather, temperature and long-term storage.

(7) This next item could generate some controversy, but DON'T START YOUR BIKE WHILE IT'S IN STORAGE unless you plan on riding it for at least 30 minutes. Refer to the "change your oil" item above and remember that one of oil's jobs is to remove contaminants from inside the engine. If you don't ride the bike long enough to get the engine up to its full operating temperature and keep it there for 10 to 15 minutes, you're going to do more harm than good to your engine.

If your bike's not hooked up to a battery tender, you'll also be damaging the battery's ability to hold a charge. Most motorcycle electrical systems do not properly maintain a battery when they idle for a long time, and indeed, idling for a long time could actually deplete the battery.

It may go against every instinct you have, but if you're storing your motorcycle for a month or more, just store it. Let it sit. Don't start it.

(8) Cover your motorcycle. If you're storing it outdoors, use a heavy-duty, all-weather cover and secure it against wind. If it snows, brush the accumulated snow off your bike as soon as you can - after taking a photo, of course!

If you're storing it indoors, use an old bed sheet – flat or fitted doesn't matter, but a fitted sheet (the kind with elastic corners) might stay in place a little better. With indoor storage, all a cover is doing is keeping dust and dirt off the bike – and maybe keeping curious passersby and children from fiddling with it.

(9) Read about motorcycles and motorcycling. I recommend David Hough's Proficient Motorcycling and More Proficient Motorcycling as well as Mark Barnes' Why We Ride: A Psychologist Explains the Motorcyclist's Mind and the Relationship Between Rider, Bike and Road for starters. Hough's books will help you visualize riding techniques that could improve your riding (and maybe save your life), while Barnes' book will get you thinking about being a motorcyclist.

Reading doesn't have to be all educational, though. If you like bawdy tales of the life of a motorcycle fanatic, check out two books by Jack Riepe – Conversations With a Motorcycle and Motorcycles Speak Louder Than Words. If your tastes run more to the documentary than the torrid, you'd be hard pressed to do better than Neil Peart's Ghost Rider: Travels on the Healing Road.

There are dozens, if not hundreds, of books you can read that will educate, inform and entertain you while the weather is keeping you off your motorcycle.

(10) Exercise and pay attention to nutrition. Riding a motorcycle can be strenuous physically, and the better prepared your body is for it, the more enjoyable it will be. Work on your core, and if you plan on riding off-road, work on your legs and upper body as well. Cardio training is good for your overall health, so don't neglect that. Paying attention to your neck muscles can help you hold your giant head up all day, especially if you wear a flip-front helmet (they tend to be heavier than other helmets simply because of the hinge and lock mechanisms).

The off season is a great time to reset poor eating habits by doing some research and paying attention to what you're putting in your body. Increase your intake of green, red, yellow and orange vegetables and try to limit your carbohydrate consumption. We all know that food choices can suffer when we're on the road, so using the off season to focus on nutrition will help you build healthy habits that can do you (and your family) a world of good.

Note: I consider avoiding cheap beer an essential aspect of eating right. Beer is packed with carbohydrates and calories, so if you're going to indulge, you may as well do so in a fashion that imparts as much pleasure as possible. Life's too short to drink crappy beer!

BEFORE YOU RIDE AFTER STORAGE

(10) Check everything about your bike. If you washed it carefully before putting it away, fixing any problems as you came upon them, your bike should be in tip-top condition and ready to go.

You should especially check your air box. Indoor storage and long periods of inattention are conducive to rodents infiltrating your motorcycle, and animals such as mice and squirrels love air filters and the spaces behind them. It doesn't take any time at all for a family of rodents to take up residence in your air box, and often you'll discover they found your air filter a delicious addition to their diet.

Inflate your tires to the recommended specification before riding. If you've stored the battery outside the bike, reinstall it. Check your foot pegs, foot controls, hand controls and hand grips for blockage or deterioration, and replace anything that has cracked or worn.

Last but certainly not least, check your gear. If your helmet has reached the end of its service life, replace it; don't forget to check your visor(s) and helmet liner, too, as replacing either or both of these things could extend the functional life of your helmet. Check the armor in your riding suit (or jacket and pants) and replace any of the pieces that may have deteriorated. Replace the insoles in your boots, or get new boots if necessary. Scotchgard your textile gear to renew its water-resistant qualities, and note that it might be time to replace your gloves as well.

Get your head on straight, turn the key, thumb the starter button and ride off into the sunset. Run that tank of treated gasoline through your bike, and fill up with high-quality gasoline and do it again. If your bike is running a little rough after the first tank, add some fuel system cleaner to the second tank and see if that helps. If it doesn't, you may need to pull the carburetors or fuel injectors and give them a manual cleaning.

Now that you've successfully survived off-season motorcycle storage, it's not a bad idea to think about building your riding skills by taking a training course. There are a number of them available, so ask your friends and do your research.

If you have any questions, feel free to reach out via email to TechQuestions@bmwmoa.org.

WRENCH – noun – a hand or power tool for twisting or turning a bolt until its head snaps off

Now that we've gotten that out of the way, let's combine those two words into what is one of the most important tool in any amateur or pro mechanic's kit: the torque wrench.

Conrad Bahr, born in 1872, found himself working for the New York City Water Department in 1918. One of the frustrating aspects of his job down in the steam tunnels and sewers under the city was coming across fasteners that were too tight (making it difficult to loosen them) or too loose, which allowed leaks and other problems.

To address these issues, Bahr had an idea for a tool that allows anybody, no matter how strong they may be, to tighten a fastener to a specific point and no further, thus ensuring not only consistency across a specific application, but a level of precision that would allow engineers to more carefully design the systems used in everyday life. Bahr and George Pfefferle, an engineer and inventor with the S.R. Dresser Manufacturing Company, filed a patent application for their "torque measuring wrench" in 1935.

The reasoning behind the torque wrench was, as Bahr wrote in his patent application, to prevent "the application of excessive strain to bolts" and to ensure proper tightening of fasteners because "The physical strength of operators varies, and the leverage at which their force is exerted may frequently vary and generally it has been found by experiment that it is practically impossible for an operator to judge with any reasonable degree of accuracy to what a degree of strain a bolt is tightened, or to secure any uniformity in the tightening of bolts of a series."

Being able to tighten a bolt or a nut to a specific level and do so consistently is a critical part of our lives as motorcyclists, and I think about that every time I tighten the five bolts that hold the rear wheel of my 2005 R 1200 GS to the rear wheel carrier with a force of 60 Newton-meters (44 foot-pounds). The simple process of accurately tightening those bolts (in a star pattern, of course) helps to keep my bike upright and handling in a predictable fashion through every mile.

Many of us think that we can estimate the proper torque with our hands, eyes and mind, somehow feeling the proper time to stop tightening a fastener. This feeling is so pervasive among motorcyclists that I did a semi-scientific study in 2015, engaging six friends and a professional motorcycle mechanic to test my hypothesis that when it comes to tightening a fastener to a specific torque value, human beings are largely incapable of accurately determining when to stop turning the wrench. In my experiment, the participants were able to hit the proper torque—again, without using a torque wrench—in just 11 percent of the attempts. In 77 percent of the attempts, the fastener was under torqued, which won't result in a stuck or broken fastener, but could result in a fastener that gives way under load, especially on something as critical as the lug bolts for the rear wheel. Based on those results, my conclusion was that using a torque wrench every time on every critical fastener is of paramount importance. (You can read the testing torque by hand article if you like.)

Because our motorcycles use the metric system, torque values for them are listed in Newton-meters. A Newton-meter is the force of one Newton applied perpendicularly to the end of an arm one meter long. A Newton measures the force that gives a one-kilogram mass an acceleration of one meter per second per second; it's named after Isaac Newton, the father of physics and calculus, in honor of his Second Law of Motion. The U.S. equivalent is pound-feet, but that seems awkward to say, so we often say foot-pounds.

Torque wrenches measure that force, and because it's rare to find a torque wrench with a one-meter-long shaft, they are calibrated to function at whatever length they are. Most of us who already own a torque wrench have a click micrometer wrench. It functions by way of a spring; the handle twists clockwise and counter clockwise to reach the desired torque setting, and when the twisting force reaches that point, it produces and audible and tactile "click" that lets the user know to stop twisting. Click micrometer torque wrenches are generally affordable and easy to manufacture, but they require that the tension be released after use or they could drift out of spec during storage.

Many professional mechanics use split-beam torque wrenches, primarily because they are faster to set and don't require the same tension release as the twist-handled click micrometer wrenches. You just release a small lock lever, turn the dial to the desired setting, close the lock lever and twist away. They produce an audible click, but not a tactile one you can feel through the handle. They are easier to use, but more difficult to manufacture and therefore carry a higher consumer cost. Typical brands like Snap-On can cost several hundreds of dollars, but the upside is you can get them used in pawn shops or on eBay and send them back to the manufacturer to have them recalibrated and therefore save considerably over the cost of buying a new one.

No matter the type of torque wrench you buy, commit to using it on every critical fastener you tighten. Look up the torque spec and stick to it; trust me when I say you and I do not know better than the engineers that designed the systems and specified the torque values. There's something both satisfying and comforting knowing you're rolling down the road on wheels that have their lug bolts, axle bolts, fork tube pinch bolts and brake caliper mounting bolts securely fastened and tightened to the proper torque values.

Check out the new NICHT UBER MAX YouTube Channel for tech videos and repeated admonitions to use your torque wrench.

All batteries work in the same fashion and contain the same basic components, which are an anode, a cathode and the electrolyte. Electrons produced by the electrolyte flow from the anode to the cathode, creating the electrical power we use to start our motorcycles and power our add-on devices like heated jackets and GPS units.

This motorcycle battery was left on an automotive battery charger overnight - luckily it was not installed in a motorcycle at the time!

First up is that one battery is “better” or “best” for your motorcycle. The truth is that as long as the battery does what it’s supposed to (start your motorcycle), lasts as long as you expect it to (usually three to five years) and fits your budget, that is the best battery for your motorcycle.

Second: gel batteries and AGM batteries are not the same thing. Both are lead-acid batteries, but their similarities with old car and motorcycle batteries that had to be periodically topped up with distilled water largely end there.

Gel (or gel-acid) batteries keep the electrolyte (the solution of sulfuric acid and distilled water) suspended in a gel state. Absorbed glass mat (AGM) batteries are a more advanced form of battery, but are often confused with gel-acid batteries because of misinformation or misunderstanding, as their electrolyte is absorbed into fiberglass plates, or mats. It’s often easier to simply refer to both gel and AGM batteries as one or the other, but they are significantly different.

Gel batteries add sand (silica) to the electrolyte solution to turn it into a thick paste, thus creating a spill-proof battery that can be installed at just about any angle. Gel batteries are well suited for deep cycle use and generally have a long life. They’re not as susceptible to internal corrosion as wet cell batteries, so they usually last a long time. The biggest disadvantage to gel batteries is that they can be damaged by high temperatures, which can harden the gel and cause it to shrink away from the plates inside the enclosure, thus adversely affecting the battery’s performance. Gel batteries unfortunately do not function well below freezing (32 F / 0 C).

Gel batteries are quickly and easily damaged by overcharging, which dries out the electrolyte paste and creates pits or holes in the gel that degrade its function. Special chargers are available to keep gel batteries properly topped up.

It might be confusing, but the AGM battery is also a sealed lead-acid battery, it’s just that its electrolyte (the sulfuric acid + distilled water mix) is suspended in a series of plates made of polyester and/or fiberglass. This not only keeps the electrolyte evenly distributed throughout the battery no matter what angle it’s at, but it prevents any leakage or spilling if the bike is anything other than upright.

One of the reasons AGM batteries work so well for motorcycle applications is because the cells are constructed under pressure and remain in their compressed state inside the battery housing. This is why AGM batteries are smaller than traditional wet lead-acid batteries, and also means that they handle vibration better, resulting in a battery that can handle the rigors of even the most off-roady of off-road motorcyclists. In addition, AGM batteries recharge more efficiently because of how the electrolyte is distributed, which means that when properly cared for, an AGM battery will last much longer than a traditional wet lead-acid battery.

On paper, AGM batteries appear to be the best for motorcycles because of their low self-discharge rates, hearty construction, low susceptibility to sulfation, ability to function in low ambient temperatures, and resistance to damage and failure when deep cycled. AGM batteries require a purpose-built charger, however, as they are easily damaged by improper charging practices. I’ve been using an OptiMate charger for a number of years with excellent results, as all my motorcycles have AGM batteries in them.

The reason many people confuse gel and AGM batteries is because they are similar in many of their characteristics. Their chemical processes are identical, in that oxygen produced by the positive plate is absorbed into the negative plate, which subsequently produces water (instead of hydrogen); this is why we don’t have to top them up like a wet lead-acid battery.

Lithium-iron batteries are a variation on the lithium-ion batteries used to power consumer electronics like laptop computers and smartphones. Their chemical notation, LiFePO4, means that for every atom of lithium (Li) present, there is one atom each of iron (Fe) and phosphorus (P) as well as four atoms of oxygen (O4). When phosphorus and oxygen exist together in a 1:3 or 1:4 ratio in the same molecule, that molecule is called a phosphate. A lithium-iron battery contains inorganic phosphates, while organic phosphates are used in herbicides, insecticides and nerve agents. Organic phosphates are toxic to most insects and animals, including humans. For the remainder of this article, we’ll refer to lithium-iron batteries as LFP, which stands for lithium ferrous phosphate, the easy-to-say version of LiFePO4.

LFPs are currently the safest, most fire-resistant and most powerful form of rechargeable lithium-based battery, but because the technology is new, they are difficult and expensive to manufacture. The biggest benefit of the LFP battery is that its discharge rate remains consistent almost until it is completely discharged, providing a steady, reliable source of power. The disadvantage of this is that you get almost no indication that the battery has reached the end of its functional service life. One day it works perfectly, the next day it’s worthless.

When it comes to myths and LFP batteries, there are many going around, so let’s take a look at them and see if we can get into the differences between AGM and LFP.

Myth: Lithium batteries are lighter than AGM batteries

This isn’t a myth, it’s true. Lithium batteries tend to be smaller in size and lighter in weight than AGM batteries used for the same application. A typical AGM battery for a BMW motorcycle weighs about 15 pounds, while a lithium battery for the same application weighs just under five pounds. While this may be attractive for a race bike, where every ounce is critical, an R 1200 GS weighs 580 pounds with an empty gas tank! Saving ten pounds on a 600-pound motorcycle should probably not be the primary consideration for choosing a battery.

Myth: LFP and AGM batteries are the same

If this were true, we’d call them the same thing. They’re quite different, and in fact, not understanding these differences can result in a damaged battery. A fully charged AGM battery will show a voltage of about 12.8 volts. An LFP battery that reads 12.8 volts, measured across the terminals and with no load on the battery, is down at least a full volt from its fully charged state. This is why a lithium battery reading at 12 or 12.1 volts will have trouble starting the motorcycle.

Myth: An LFP battery won’t start my bike if it’s cold outside

A clear disadvantage of LFP batteries is that they often have difficulty starting a motorcycle in cold weather. One way to get around this problem is to turn the ignition on, wait for 30 seconds or a minute, and then try to start the motorcycle. It may take a few attempts to start the bike with a LFP battery when the weather is cold, so patience is often rewarded. A better solution is to combine the above with keeping your LFP battery on a proper charger.

Myth: An LFP battery has a higher capacity than an AGM battery

A standard AGM battery will have six cells of about two volts each, while a standard LFP battery has four cells of about three volts each. In other words, both are 12-volt batteries. However, when you look at battery capacity, the number to look at is called “amp-hours” (Ah), which lithium battery manufacturers derive from a “lead equivalency” (PbEq) rating. A battery with a PbEq of 20 may only have six amp-hours of capacity, which is actually less than an AGM battery—up to four times less! What happens as a result is that a rider may charge their GPS, comm system, Go Pro camera, cell phone, etc. and end up surprised that their LFP battery is dead after just one or two days.

The solution to this is to check out the true amp-hour rate that some LFP battery manufacturers are starting to list on their packages. A standard Odyssey AGM battery for a bike like a K 1600 GTL has 16 amp-hours of capacity, so compare an LFP battery to that.

Myth: It’s impossible to overcharge a lithium battery

Maximum voltage for an LFP battery is 14.6 volts. Higher voltages will damage the cells, degrading their ability to be recharged. More importantly, damaged cells in a lithium battery may overheat when recharged, which could not only damage the other cells in the battery, but could, in rare cases, start a fire and do far more damage.

Myth: Lithium batteries must be kept fully charged at all times

LFP batteries tend to function best when kept between 13.05 and 13.6 volts, but if they are discharged below 10 volts, that messes with the chemical balance in the electrolyte. An LFP battery discharged below 13 volts is unlikely to even start the motorcycle, which would lead many riders to try to jump or bump start the bike. This is a mistake; the unique charging requirements of an LFP battery (see the next myth) mean that bump starting the bike and engaging the motorcycle’s onboard charging system is likely to damage the LFP battery’s cells, causing them to eventually overheat and possibly catch fire.

Myth: Any charger will do for LFP batteries

If you buy an LFP battery for your motorcycle, don’t cheap out on the charger. It is critically important to buy a charger that is optimized for use on LFP batteries for a number of reasons. The most important reason is that the proper charger “understands” the LFP battery’s unique charging requirements, which are not the same as those for a lead-acid battery—and that includes AGM batteries, which use the same basic electrolyte as your grandfather’s vintage pickup truck’s battery. Bikes with “always on” electronics (clocks, alarms, etc.) will discharge an LFP battery fast; remember that while the lead equivalency may be high, the actual amp-hour capacity is low, and while a good LFP battery charger can bring a discharged battery back from as low as one volt, it has to be done properly, by using low current until the LFP is above 12.8 volts, when it can then be hit with higher current for faster charging. A lead-acid battery charger uses high current at low voltage, which could easily damage that expensive LFP battery.

Both AGM and LFP batteries benefit from being on a charger when the motorcycle is not being ridden, but it is more important for the LFP batteries, which also MUST use a purpose-specific charger. If you have a mix of AGM and LFP batteries in your motorcycle fleet, that means you need more than one charger, and don’t mix them up. In the words of Ghostbuster Dr. Egon Spengler, “That would be bad.”

It’s important to note that BMW Motorrad does not spec LFP batteries for their new motorcycles; they continue to use AGM batteries, even on the standard S 1000 RR. While I’m certainly not opposed to updating my motorcycle with new technology, the battery is one of the things that I don’t mess around with and tend to stick close to the OEM specs. Nobody wants to look down while they’re riding and see flames between their legs.

Those miles add up so quickly that it is easy to go beyond the 10K interval often recommended for servicing the final drive splines on a high-mileage K 75. When I bought my K 75 in 2009, the seller put me at ease by telling me the bike had a recent spline lube; the real question was what condition those splines were in. To answer that question, there is no substitute for disassembly and visual inspection.

After owning my K 75 for a few months I brought it to a trusted mechanic for a rear spline lube just in case the seller wasn’t altogether honest with me. After removing the final drive, the mechanic showed me the compromised condition of the splines, which are supposed to have sharp rectangular edges on each individual spline. Mine were showing unmistakable signs of wear, rounding of the edges. This news put me in a downhearted state as I really wanted my K 75 to be ready for the long haul with few worries. Many of us seek unlimited years and miles of riding ahead when we choose a BMW.

I replaced my final drive and drive shaft with units having new or like-new splines. I then decided to build a device to keep me on track with rear spline maintenance, and get the most miles possible on my replacements. The rear end of the drive shaft has the output splines, while the final drive has the input splines. This pair is what I am focusing on. At the front of the drive shaft and between clutch and transmission are other important splines, but the critical maintenance of those are not being covered in this piece.

The tool I built can be described as a final drive stand, or a jig, a cradle, and a dolly. It is an aid in all three steps of servicing the rear splines of a monolever K bike like mine.

Step 1: Remove final drive from drive shaft

Rear wheel has already been removed, brake calipers secured, and rear portion of speedometer cable disconnected and secured.

The stand/cradle attaches to the final drive with two plastic 12-inch zip ties before removal. After the shock absorber is unbolted, the four Allen bolts connecting the final drive to the drive shaft are removed. The stand, with the final drive mounted upright, is then rolled down the ramp which has the same slope as the drive shaft in its running position. The stand in no way replaces the need to prop up or strap the drive shaft in position before disassembly.

Step 2: Cleaning, inspection, and lubing the splines themselves

This is the most important step. With the final drive upright and secure in the stand/cradle, this phase can be done as thoroughly as needed without the risk of kicking over a final drive leaning shakily against the wall while it sits on the garage floor. Solvent and an old toothbrush are good for removing old lube material, often high in molybdenum disulfide paste, a popular ingredient for lubricating splines. After cleaning both input and output splines I apply a generous amount of fresh lubricant/paste with on old one-inch paint brush that has that has lost most of its pliability.

Step 3: Reassembly

Here is where you need a third hand to spin the brake rotor slightly so the output and input splines mate and slip into place. An unsupported final drive is heavy and awkward to hold and guide, requiring both hands for many of us, but with the final drive on the stand/cradle, which is sitting on the ramp, one hand is enough. The other hand is used to spin the brake rotor.

The final drive has a beveled shape with few flat surfaces to use when molding a jig. I did it in many steps. I cut out wood and metal, bending different gauges of wire to match the bevel. I then covered the bent wire with fiberglass cloth and multiple layers of epoxy resin and filler. With great care I avoided contaminating the final drive exterior (or interior) with uncured epoxy.

The sheet metal inner surface of the stand, facing the brake rotor, must be completely flat and smooth, so as not to damage the rotor in motion. Look for a groove at the bottom of the cradle where the final drive drain plug fits undisturbed.

Construction of the tool required a lot of work. A 3D printer might provide a means of reproducing the molded cradle portion of this project. The other parts are not that hard to build and I expect there are riders who could offer improvements.

Originally published in Between the Spokes, June 2015. Republished courtesy of BMW Bikers of Metropolitan Washington.

I am the kind of person that holds a grudge. I'm not proud of it, but it's part of my character nonetheless. There's a gas station I won't go to in Dale City, VA because a clerk there insulted my girlfriend in 1990. I didn't even marry that girl.

BACKGROUND

Given my ability and willingness to hold a grudge, it may not surprise you to learn that I'm still fuming a little bit over the rear wheel flange recall, especially the part where I feel like BMW Motorrad shifted the blame for the problem (construction, rather than assembly – but that's an exploration for another time) onto dealer technicians and BMW riders who perform their own maintenance.

To refresh your memory, here's a quote from the recall notification published by the National Highway Transportation Safety Administration (NHTSA): "In the affected motorcycles, the rear wheel mounting flange may crack if the rear wheel mounting bolts are overtightened." Maybe it's just me, but I find it just a little insulting that BMW assumes I can't use a torque wrench.

I did start thinking, however, that maybe they have a point. I'm sure no qualified technician would mount a rear wheel without properly torquing the mounting bolts, but I have to admit that it's a lot easier to spin the bolts on gudentite when you're sitting on the floor of your garage (or on the side of the road) and the torque wrench is out of reach – or not even around.

THESIS

The hypothesis that emerged – one that would support BMW's assertion that the problem with the aluminum flanges is due to user/technician error rather than the engineering of the part or factory assembly – is that human beings cannot tighten a fastener to a given torque point without an actual torque wrench. I made the assumption – again to support BMW's position on this specific recall – that humans will overtighten fasteners if they don't use a torque wrench.

Greg, Sunday, Wes, Kurtis, Katie, George and Kermit.

TESTING

I gathered eight people for this experiment:

• Myself – 45 year old male, 20 years of riding experience, and enough confidence, skills and tools to perform most regular maintenance tasks on my BMWs ('05 R 1200 GS and '98 K 1200 RS). However, I go to a mechanic for difficult things like replacing the rear wheel flange. I functioned as the "untightener" for this experiment, using a beam-type torque wrench to measure how much force (torque) it took to loosen the bolts we tested.
• Sunday – 42-year-old female that doesn't ride motorcycles, but has experience with fixing things around the house (including the use of power tools).
• Kurtis – 37-year-old male with 11 years of riding experience. He claims "minor" wrenching experience – oil changes and the like.
• Katie – 34-year-old female with three years of riding experience that does no wrenching at all. She is, however, an electrical engineer with a solid knowledge of mechanical matters.
• Dave – 46-year-old male with 25 years of riding experience. He's restored a vintage BMW and works on his own bikes regularly.
• Kermit – 52-year-old male who has been riding since age 5. He has his own motorcycle lift and a lifetime of practical mechanical experience that he's not afraid to use.
• George – 45-year-old male with 25 years of riding experience; he makes his living as an independent motorcycle mechanic and has worked as a master technician at motorcycle dealers as well.
• Greg – 50-year-old male with 25 years of riding experience who does "a little" routine maintenance.

I chose the settings to test and George determined the best fasteners relevant to BMW riders to test them on. The valve cover bolts on a K 1200 RS engine should be tightened to 9 Newton-meters (Nm), but since we were using a blown engine, we tested it to 10 Nm. The front axle pinch bolt on an R 1100 RT goes to 22 Nm, so that was perfect to test 20 Nm. The front brake caliper mounting bolt on the same bike goes to 40 Nm. The rear wheel mounting bolt on an F 800 S goes to 60 Nm, and this is the same bolt and torque specified on many of the motorcycles affected by the recall. This specific motorcycle was built outside the recall range, so it has a steel flange already, but the torque spec is the same. Finally, the rear wheel mounting bolts on the RT go to 105 Nm, perfect to let us test 100 Nm.

We used a variety of standard hand tools (ratchets, Torx and hex sockets, standard sockets, breaker bar, etc.) for the testing. We used two types of Snap-On torque wrenches, one that is a typical "clicker" wrench that gives a physical indication (a click you can feel through the handle) when you reach the torque setting and another with a split-beam mechanism that gives an audible click, but offers no physical feedback when you reach the torque setting. Both of those wrenches retail for about $300. The wrench used to test release torque was a CTA beam-type torque wrench that cost about $25.

The test procedure went as follows:

1. Each participant except Greg and George used a torque wrench to tighten the fastener to the appropriate torque to get an idea of what the appropriate torque feels like. I loosened the fastener after each test.
2. Each participant used a standard ratchet wrench (or breaker bar for 100 Nm test point only) to tighten the fastener to what he/she believed was the appropriate point.
3. I used the beam-type torque wrench to loosen the fastener, noting at what level the fastener started to come loose. The CTA torque wrench is calibrated in Kilogram-meters (1 kg-m = 9.80665 Nm), so I wasn't able to tell each participant how well they did as we went along.
4. We started at 10 Nm and proceeded to 20, 40, 60 and 100 Nm.
5. We rode to lunch – of course!

Kermit seeing what 10 Nm feels like on a blown K engine.

One thing we determined that we couldn't test or allow for is that it takes a little more torque to overcome a fastener's grip than the specified torque for tightening the fastener. For example, if a bolt is tightened to 100 Nm, it must take at least 100.1 Nm to loosen the fastener. We neither collectively knew nor was I able to find through research a formula to account for this, so our experiment must be taken with a grain of salt. By having just one person doing all the loosening, we at least minimized any variances in "break-free" torque that could have come from different strength levels or techniques had we used more than one person to loosen the fasteners.

The results for each target torque were as follows:

George, our professional mechanic, and Greg, our control, were the only two participants who didn't test each fastener with a torque wrench to get a feel for the appropriate tightness at each test point. Greg consistently under-torqued on his turn, just barely at lower levels, but far more significantly at the two highest points. George under-torqued three settings as well, but nailed 40 Nm and overtorqued by nearly 20% at 100 Nm. Our most accurate participant was Sunday, who has never worked on a motorcycle in her life, but fixes anything and everything around the house; she hit 10 and 60 Nm exactly.

Forty Newton-meters seemed to be the most difficult to gauge, with five of our seven participants falling at least 25% under spec. Two of them were 50% under spec at this test point.

Katie testing at 20 Nm using the fork pinch bolts on an R 1100 RT.

With the exception of the attempts at reaching 100 Nm without the aid of a torque wrench, nearly every participant under-torqued every fastener; only one participant hit torque marks precisely at 10, 20, 40 and 60 Nm. Nobody hit 100 Nm, but everybody was pretty close with the exception of George (20% over) and Greg (25% under).

CONCLUSION

In general, we humans were more likely to under-torque a fastener than we were to over-torque it, at least at lower specs. The only time the participants went over the specified torque at all was at the highest spec, 100 Nm.

My conclusion in this semi-scientific torque targeting experiment is exactly what I thought it would be when I set out on this path: It is always better to use a torque wrench when working on your motorcycle. The result that surprised me, though, was that the participants were more likely to under tighten a fastener than they were to overtighten it, something that seems to fly in the face of BMW's assertion that the flange cracks are somehow the fault of dealership technicians and shade-tree mechanics all over the entire world.

From a statistical standpoint, we measured 35 data points. Of those, only four resulted in torque values above the target point. This is a failure rate of 11 percent. Given that I have had two flange failures (a failure rate of 66 percent – two out of three), I find it disingenuous that BMW implies that it's my fault that my rear wheel flanges developed cracks. I also can't explain (yet) how overtightening the wheel bolts causes cracks where the brake disc mounts. I'm working on that, though, and hope to have a follow-up article about it someday.

We joked with George, our pro, that he would probably be the most accurate since he has spent over half his life working on motorcycles. He replied that he didn't need to go by feel because he always uses a torque wrench. This is sage advice well supported by this experiment. When you work on your motorcycle, always use a torque wrench. Quality torque wrenches can be had through many outlets, and don't be afraid of a beam-type torque wrench. Though they are low-tech feeling and looking, they never need calibrating and can be used both to tighten and loosen.

Once I had the data we needed, we tested a couple of other things. We discovered it took just 30 Nm of force to strip the K 1200 valve cover bolts (10 Nm spec). We also discovered that it's nearly impossible to get the rear wheel mounting bolt on an R 1100 bike to the proper torque spec (105 Nm) using just the BMW-supplied tool. We agreed that Greg was probably the strongest among us, and using just the lug wrench from the stock tool kit, he could only get those bolts to 78 Nm using all his strength and leverage. Using the extension tool supplied in the stock tool kit allowed most of the participants to torque those bolts to near the appropriate spec, though.

SIDEBAR: WHAT IS TORQUE?

When it comes to motorcycles, there's two ways we use the word torque, and they're both related to force.

The first way we talk about torque and motorcycles is usually relayed alongside horsepower. For example, my 2005 R 1200 GS left the factory with 100 horsepower (hp) when the engine runs at 7,000 revolutions per minute (rpm) as well as 115 Nm of torque at 5,500 rpm. Horsepower is actually a function of torque, but that's a discussion for another time.

The other way we talk about torque is when we need to know exactly how tight to go with a fastener.

No matter which way we're talking about torque, it's all about twisting force being applied to something. In the case of 115 Nm of torque at 5,500 rpm, it's the twisting force being laid out by the crankshaft – and thus applied to the driveshaft. In the case of the 60 Nm specification on the rear wheel mounting bolts on my GS, it's the point at which the engineers (and all the science behind what they do) say "this bolt is tight enough that, given the materials it is made of, passes through, and connects to, it can be expected to stay tight under nearly all circumstances."

SIDEBAR 2: WHAT THE HELL IS A NEWTON-METER?

Science and math are hard, and a lot of that we can blame on Isaac Newton. After all, he invented both physics and calculus. He got this measurement of force named after him due to his Second Law of Motion, which states that Force equals Mass times Acceleration (F = ma).

When we're talking about crankshaft torque, a Newton is the measurement of how much force is required to accelerate one kilogram of some mass to a speed of one meter per second squared. In other words, 1 N = 1 kg * m/s2.

When we're using a torque wrench, however, we're not measuring speed, we're measuring rotational force. In that instance, picture an arm one meter long; a Newton-meter is the force of one Newton applied perpendicularly to the end of that arm. This is one of the reasons torque wrenches are different lengths – leverage affects force, so the length of the torque wrench has an effect on how that wrench measures torque.

SIDEBAR 3: TYPES OF TORQUE WRENCHES

Top to bottom: beam-type TR, split-beam TR, Snap-On click micrometer TR, Craftsman CM TR, 1/2" breaker bar (for perspective – it's 15" long).

The oldest, simplest and cheapest torque wrench is a beam-type one. There are no moving parts and it never needs calibrated. As long as you don't break it, it can last a lifetime. They require a little finesse to use (try to keep the handle floating at all times) and they're not the easiest to read; after all, it's just a pointer hovering over a scale. They don't ratchet, and they're usually long (for better leverage at high torque requirements), so they can be awkward to use. Another con of a beam-type torque wrench is that they're only as precise as the scale printed on them; they may go 10-20-30 Nm, requiring you to estimate where 22 Nm actually is.

The torque wrench that's probably most common among shade-tree mechanics is the click micrometer type. This type of torque wrench has a handle that twists in and out, with the torque scale engraved on the shaft. When you twist the handle to the desired torque, you're tightening a spring inside the shaft. When you use the wrench and reach the desired torque, the force you're using overcomes an internal mechanism (under tension from the spring) and you feel and hear a "click!" as the wrench moves. There are many different types of click micrometer torque wrenches at all different price points, but they all have the same pros and cons.

The pros are that they're easy to use and generally accurate to within a few percentage points of the target torque. There are several cons, starting with your wrist getting tired from all the twisting – you always have to reset them to a low torque or you risk damaging the spring and thus ruining the wrench. Leaving them set to zero could potentially damage them as well. Click micrometer torque wrenches need to be treated with some care; a big drop can damage the internal mechanism, necessitating repair or replacement. Another con is that to change from a higher to a lower torque setting, you need to go below the lower torque setting, then crank back up to it. If you're doing a lot of different tasks, this gets tiring pretty quick.

A split-beam torque wrench also gives you a click! to let you know you've reached the torque set on the wrench, but it's an audible sound rather than a physical thing. These are easier to use than the click micrometer wrenches – you just spin a little dial to the correct setting, and then lock it in with a little cover that prevents the knob from spinning again. There's no heavy spring to twist against and you don't have to remember to release the tension when you're done using it. The main downside to split-beam wrenches is that they must periodically be calibrated.

There are also a variety of torque wrenches with digital readouts, but the digital readouts are built into either click micrometer wrenches or split-beam wrenches. Personally, I stay away from these, because the digital readout is another thing to worry about – it may not be waterproof, the battery could die, the screen could crack. They're also more expensive than their analog counterparts, sometimes by a factor of two or three. The advantage of a torque wrench with a digital screen is that you can use them in darker conditions, which is probably more useful if you're working in a car's engine compartment than if you're working on a motorcycle. Many of these digital torque wrenches can switch from inch- or foot-pounds to Newton-meters, relieving you of having to do math or squint at markings etched into the shaft of a wrench.

Other types of torque wrenches are dial type wrenches (not unlike the beam-type wrenches, but laid out with a dial instead of a linear scale) and torque angle wrenches. A torque specification that looks like 28 Nm + 45 degrees requires that you first torque the fastener to 28 Nm, then use a torque angle wrench to turn the fastener another 45 degrees. There are other types of torque wrenches unsuited for motor vehicle use, such as the hubless type used by plumbers.

In addition to the CTA beam-type wrench used in this experiment, I have two Craftsman click micrometer torque wrenches. Both are 3/8" drive and marked for both foot-pounds and Newton-meters; one ranges from about 10 to about 120 Nm, the other (shorter) one ranges from about 2 to about 30 Nm. They require a little math to use sometimes, as the markings don't go one by one. Markings on the twist handle combine with the markings on the shaft to allow the user to get the precise torque setting desired.

After doing this experiment, I went on eBay and bought myself a Snap-On split-beam torque wrench just like the one George has. It's so much easier (and faster) to use than the click micrometer wrenches that I couldn't resist. I paid $75 for it and another $50 to get it calibrated. That is more than I paid for either of the Craftsman wrenches (MSRP $80, usually on sale for $35-60), but it will be worth it simply to not have to twist those handles all the time.

From the campaign bulletin:

"As a result of ongoing field observations, BMW Motorrad has determined that the fixed fork tube (stanchion) of the R 1200 GS (K50, K50/11) and R 1200 GS Adventure (K51) can be damaged due to unusual incidents. Such high stress can be caused for example, when riding over an obstacle, during a fall or when driving through deep potholes. Resulting damage to the fixed fork tubes manifests itself through a gap between the stanchion and the press-fitted, top seal plug.

An inspection process along with a repair procedure has been developed. All affected motorcycles must receive one of the two repairs outlined in this bulletin. Customers will be notified by mail by BMW Motorrad USA."

Should an inspection turn up the need for a repair, BMW Motorrad recommends one of two repair options, as follows:

1. Installation of a fork tube bushing onto the existing fork tube, or
2. Installation of a fork tube bushing onto a new fork tube, or the replacement of a fork tube with a new one that already has the bushing in place

Owners of motorcycles that are affected by this technical campaign are urged to contact their dealers, but the list of VINs affected may not be available to dealers until 30 June - so give your dealer a break if they don't know if your motorcycle is affected.

In this article, I will describe replacing the internal assembly within the master cylinder body of my 1995 K 75. I can only assume that this procedure will work with similar non-ABS K 75 models with rear disc brakes. Please refer to the following public-domain schematic of the rear master cylinder as I will be using terminology from it to avoid confusion.

After noticing brake fluid leakage within the rubber boot, I concluded that leakage was likely occurring around two rubber seals in the piston assembly, so I weighed my options. I could purchase and replace the entire cylinder (approximately $350 new) or purchase a rebuild kit and reuse the cylinder body, which would only cost $95.

I opted for the rebuild to keep costs down and ordered and received the kit, part # 34 31 2 311 064. I chose to reuse both the hose that feeds the fluid into the cylinder as well as the flexible brake hose to the rear caliper brake assembly. While the Clymer’s manual is a good guide, there were several details or shortcuts I learned that are absent from the manual’s procedure. An assistant and I completed this in approximately two hours and neither of us is a mechanic, so the repair can certainly be done by almost anyone who has the tools. I will not describe exact tools needed, but metric Allen wrenches, rubber tubing, open-ended box wrenches, DOT 4 brake fluid, rags, and a bungee cord sufficed for me.

The procedure:

1. Remove three bolts holding the right foot peg base to access the cylinder body. If your machine has a bag rack attached (mine does), remove the additional two bolts. Do not dangle the detached foot peg base, as it will strain the brake hoses. Attach a bungee cord to suspend the removed foot peg base. Note: Ensure that the small spring attached to the foot pedal is accounted for and/or removed for later reattachment; this is not depicted in the manuals I consulted.
2. Remove two bolts attaching the cylinder body and carefully let it dangle.
   
3. Remove rubber boot from cylinder body
4. Unscrew a small retaining screw on the side of the cylinder body, which will permit you to withdraw the piston assembly from the body. This assembly is the part, along with the rubber boot, that you will replace. Examine and lay out the parts in order for reference. In the following photo, the two parts that fit in the end of the assembly are called stoppers and make contact with the adjust bolt (also see the schematic, above).
   
5. Clean and flush the inside of the cylinder body to remove any contaminants and coat with brake fluid. Also, soak the new assembly in brake fluid to lubricate and soften seals for later insertion.
   
6. Insert the new piston assembly into the cylinder body, being careful not to distort one of the seals that is cup-shaped. The spring will require you to keep pressure on the assembly until you next screw in the retaining screw into the body, thus holding the assembly within the body. Note: The retaining screw fits between the two seals in the assembly, permitting movement while preventing the assembly from springing out of the body. Check that the assembly compresses and returns smoothly.
   
7. You may now replace the adjust bolt and locknut (far right in above photo) to the foot brake lever, which first requires loosening a small Allen nut in the brake lever. I did not opt to do this to save time. I inspected the original adjust bolt and it appeared to be in acceptable condition. I didn’t remove it.
8. Reattach cylinder body to motorcycle with two bolts.
9. Replace rubber boot with new one. This may require some dexterity and patience. Note: The rubber boot has a slot within the opening into which the adjust bolt’s flared end fits. This is not depicted in any manual I consulted.
   
10. Reattach spring on brake lever if necessary and depress lever to test free movement of compression and return of cylinder assembly. At this point mine was frozen and some misalignment between the stopper and adjust bolt was the cause. I removed the retaining spring and worked the movement and it realigned properly. I screwed the retaining screw down and the assembly now moved freely under the spring compression normally.
11. Visually inspect and reattach the foot peg base with three bolts and the two bolts for the bag frame if your motorcycle has the frame.
12. Bleed and then replace the brake fluid in the system with fresh DOT 4 fluid.
13. Test ride machine. At this point you may want to make any adjustment to the feel of the brake lever by loosening the locknut on the adjust bolt and moving it in or out, thus decreasing or increasing the “throw” or movement of the lever. I slightly shortened the throw.

From below, the rear master brake cylinder reattached and rebuild completed:

Anyone wishing to rebuild their own master cylinder may consider replacing the brake hoses as well as a preventative measure. My machine has 27,000 miles on it and is 22 years old. I may replace the hoses in the future. Also, do your best to avoid brake fluid contact with painted surfaces; I took my machine to the car wash and with soap, low-pressure cleaned some areas below the brake reservoir. My thanks to my assistant, Ted. Good luck to all my fellow riders keeping their K 75 motorcycles properly maintained and on the road.

Why does my 2005 K 1200 LT eat up rear tires? -Matthew M. via email

A:

Even though it looks and acts like a luxury touring machine, your ’05 LT shares a number of characteristics with the K 1200 RS, including its torque rating of 85 foot-pounds. Torque is what gets you up to speed from a dead stop. If you jump on that throttle, you’re going to wear out more rear tires than front ones.

It also depends on what you’re doing with your LT. If you’re pulling a trailer and all three cases are packed to the max with gold bars while your partner hangs out on the rear seat and has their pockets full of depleted uranium rods, you could be overloading the rear tire and causing it to wear out prematurely. As a side note, overloading your bike like this could also damage your final drive; in other words, it’s important to pay attention to BMW’s max load specification. Your bike’s “wet weight” (all fluids on board) is about 860 pounds and BMW says the GVW is 1,323 pounds, leaving you a load capacity—which includes you and your passenger—of 463 pounds. Exceeding that amount significantly can damage components, including the tires, which have their own load ratings.

Without getting into a discussion about tire preferences, you should endeavor to purchase a tire that is rated for your motorcycle and application. This seems like an obvious thing to say, but there’s a difference between “I heard these tires are great” and “This tire is rated for an 800-pound load.” Purchasing off-brand tires isn’t a great way to save money, largely because you end up replacing them more often than high quality (and more expensive) tires. In the long run, you’re likely to come out even in rubber costs, but you’re likely to install (or paying to have installed) more of the cheap tires, which eliminates any perceived savings on parts costs. The tire that’s appropriate for a sport bike isn’t appropriate for a touring bike even if the wheel sizes are the same. It’s the application that is the determining factor, not the size.

Look at your tire’s sidewall to get important information, such as max load ratings. On this Metzeler ME880, which many LT riders use, you can see it is rated for 963 pounds at 50 PSI. Most riders don’t inflate their tires to 50 PSI, but how PSI affects load rating is a conversation for another time.

Q:

George, I'm surprised at your response to Doug's question. Doug mentioned that the bike had ABS and that they had "blown out the ABS module," but you made no mention of the ABS module in your response. I know nothing of motorcycle ABS; however, ABS modules in automobiles include a pump that returns brake fluid released to control braking pressure into the pressurized system. That keeps the brake pedal from dropping out from under the driver's foot as a result of ABS activation.

Could it not be that something in the ABS module has gone awry and that fluid is being pumped back to the master cylinder, creating the leakage that Doug comments upon? If that is not possible, would it not then be appropriate for your response to rule it out?? --Brant M.

A:

Brant, The R 1100 RT used an ABS pump that, when in ABS mode, shunts the flow from the master cylinder. This prevents the lever from "going to the floor." If you stay in ABS mode long enough, eventually you will "go to the floor." Every time the pump cycles you lose a tiny bit of pressure until it reads wheel slip and reactivates. It has no way of pushing fluid back to the master.

Doug's complaint was during normal operation, not in ABS mode. During normal operation, his ABS pump is passive. If the pump were running when not needed, he would have heard it and lost pressure. I had an R 1100 RS that would go into ABS mode when not needed. The only way to stop the bike was to release the brakes, turn off the key and reapply the brakes.

If Doug had a modern, linked system (post IABSI), what you are describing is possible. In those models, a stepper motor is used to activate the caliper of the non-applied circuit. This causes a slight push back at the non-applied lever. If the lever was not adjusted correctly and the reservoir was over-filled, it would be possible to build pressure in the reservoir. Hope that answers your question.

Have questions for Nicht Uber Max? Send them to TechQuestions@bmwmoa.org.

A:

My wife (who loves me) has an identical twin sister that barely tolerates me. Your bikes are not identical.

Like my wife and her sister, your bikes have different life experiences that have brought them to this point. The transversely-mounted K 1200 engines (i.e. Japanese style inline 4) are prone to warping air box issues, which could be the reason you gave one of them backup status in the first place. A warped air box causes high idle, degrades acceleration, makes the bike hard to start, and can cause other running issues. Even if you bought a first year K 1200 S, you’d need a final year K 1300 S air box, which seems to be the best solution for these air box issues.

Knowing that this bike sits more than its sister, I have to wonder how much does it sit? BMW wants your bike ridden at least 100 miles a month, which they believe will stave off a lot of these kinds of problems. If you’re not riding it that month, you might suffer from excessive moisture in the gas tank, stratification (separation) of the fuel, gummed up fuel injectors, or deteriorated components inside the fuel tank (fuel filter, fuel lines, etc.). These are all common issues that crop up when E10 gas sits for a long time.

Start with a common fuel treatment such as Sta-Bil, Star Tron, or BMW’s fuel treatment solution and a fresh tank of high quality gasoline. Follow that up with more fuel treatment and more fresh gasoline—in other words, Ride, Fuel, Repeat. If after three full tanks in a month, the problems persist, you’re probably looking at a mechanical issue rather than a chemical one. You may need to replace some or all of the fuel tank’s internal components, fuel lines and/or injectors. Worst case, your air box may suffer from the warping issue and need replacing. (GM)

Q:

A:

I ride a 1998 K 1200 RS, so the ergonomics are going to be identical to your 1999 K 1200 RS. I’ve ridden several F 800 STs, one of them for a couple of thousand miles. I’m also only a couple of years younger than you!

I believe you will find the ergonomics between the bikes to be quite similar. They are not identical, but they both have knee-aggressive footpeg locations and similar, though not identical seat-to-handlebar reach lengths.

If you want to hang on to your K a bit longer, one thing to look at is a footpeg lowering kit. Pirate’s Lair sells one made by Verholen; it’s not cheap, but the quality is outstanding. They also sell a set of wider footpegs that the manufacturer (a British company) claims adds long distance comfort. It’s likely that between these two things, you may find some ease for your knees. Buying both kits will set you back over $400, but that’s a lot cheaper than a new bike. Make sure your kit includes both the footpeg plates and the shift lever extension (see the photo and pardon the rusty bolt!).

Given my experience with the F 800 ST, which is a fantastic bike on its own (if a little buzzy at high speeds), you won’t find any relief in the knee angles there without modifications similar to what I’m suggesting with your K bike. If you decide to go that route, check out the kit offered by Suburban Machinery for the F series bikes. (WF)

Have questions for Nicht Uber Max? Send them to TechQuestions@bmwmoa.org.

A:

Let’s begin with the assumption that you are not over the maximum mark for filling the brake fluid reservoir on the handlebar. It’s important to stay at or below the max mark (remember – NICHT UBER MAX!) because that allows expansion room for the fluid as it heats up under normal use.

On some older Ducatis, the rear brake line was routed so close to the exhaust pipe that it would heat up the fluid, causing it to expand enough to clamp the rear brake tight. This was made worse if the pedal wasn’t properly adjusted, but it was a problem either way. Since you don’t have a Ducati, though, this probably isn’t what’s going on. Thinking about those Ducatis, though, you said “run the bike.” With the Ducatis, this was an issue at idle after the bike was warmed up. Do you really mean “ride the bike,” as in this happens while you’re riding or is it happening at idle?

Since fluid is coming out the master cylinder, this gives me three ideas: the master cylinder itself, the piston that connects the brake lever to the master cylinder and your hard brake lines.

The first thing to do is check what you’ve already done, and in this instance my initial suspicion is the master cylinder rebuild, especially given that it’s an 1100. In early 1100s such as yours, the master cylinder bore was not anodized, which can promote corrosion and scoring and lead to blockages. It’s possible when the master cylinder was rebuilt that the bore wasn’t checked or properly cleaned. If there’s debris in there blocking the bore, it would prevent fluid from returning to the master cylinder, thus keeping the calipers clamped down.

The second thing it could be is the brake lever piston adjustment. If the brake lever was replaced or damaged and subsequently not adjusted to spec, then this could be keeping the system pressurized, much as if you were constantly riding the brake. When you rebuilt the master cylinder, the piston could have been slightly misadjusted or misaligned. This could partially block the return port for the brake fluid. Effectively this would keep the brake pressurized and the caliper clamped tight to the disc. This would result in the brake fluid heating up and you might see fluid seeping from the master cylinder cover as the pressure and heat cause the fluid to expand and move forcibly.

There’s a reason BMW puts red paint on the piston moved by the brake lever – they don’t want you to adjust it! If it’s not in precisely the right position, it can cause other internal components to block the fluid return hole and prevent brake fluid from flowing away from the calipers.

Third (but least likely) is that you have a problem with your hard steel brake lines. If they are filling up with plaque—not unlike an old man’s arteries do-then this would create the kind of pressure you’re seeing (as well as excess heat while riding) and cause the brakes to always drag and refuse to release. Upgrading your rubber brake lines to the stainless steel braided ones, while a good upgrade, would not solve this problem. The pressure generated by applying the brakes is subject to the principles of hydraulics in that if you squeeze fluid from a large hose into a smaller hose and that smaller hose is partially blocked with goo, the fluid will move one direction more easily than the other. So what you could be seeing here is fluid that flows to the calipers goes through the hard lines just fine, but because of possible blockages, that fluid cannot flow back through the hard lines because there is very little pressure moving the fluid in that direction. If you want to look up the principles of hydraulic multiplication of force, that may explain this concept in more depth.

Q:

Dear Nicht Uber Max: George, I'm surprised at your response to Doug's question. Doug mentioned that the bike had ABS and that they had "blown out the ABS module," but you made no mention of the ABS module in your response. I know nothing of motorcycle ABS; however, ABS modules in automobiles include a pump that returns brake fluid released to control braking pressure into the pressurized system. That keeps the brake pedal from dropping out from under the driver's foot as a result of ABS activation.

Could it not be that something in the ABS module has gone awry and that fluid is being pumped back to the master cylinder, creating the leakage that Doug comments upon? If that is not possible, would it not then be appropriate for your response to rule it out?? –Brant M.

A:

Brant, The R 1100 RT used an ABS pump that, when in ABS mode, shunts the flow from the master cylinder. This prevents the lever from "going to the floor." If you stay in ABS mode long enough, eventually you will "go to the floor." Every time the pump cycles you lose a tiny bit of pressure until it reads wheel slip and reactivates. It has no way of pushing fluid back to the master.

Doug's complaint was during normal operation, not in ABS mode. During normal operation, his ABS pump is passive. If the pump were running when not needed, he would have heard it and lost pressure. I had an R 1100 RS that would go into ABS mode when not needed. The only way to stop the bike was to release the brakes, turn off the key and reapply the brakes.

If Doug had a modern, linked system (post IABSI), what you are describing is possible. In those models, a stepper motor is used to activate the caliper of the non-applied circuit. This causes a slight push back at the non-applied lever. If the lever was not adjusted correctly and the reservoir was over-filled, it would be possible to build pressure in the reservoir. Hope that answers your question.

If you’re having a problem with your motorcycle that you’d like to see addressed, send your questions or issues to techquestions@bmwmoa.org, and we’ll address your problem in a future installment.

Frank Palmeri: How did you get into motorcycles?

Paul Heid: I started out racing motorcycles. My dad always was into bikes, and he got me started with Rupp mini-bikes. When I saw him on one I had to have one so that’s how I got started. Then he got into Hodakas and started selling them, and a year or two later I started racing.

FP: How old were you when you started racing?

PH: Like nine or ten years old. I started racing oval dirt track at eleven.

FP: When did you know motorcycles would become a career?

PH: From when I was an adult I always worked at the shop at least part time. When my parents went on vacations I used to cover for them. I never really planned on making it a career, but other jobs I had didn’t work out so well. Then in October 1984 my dad asked me to start working here full time.

FP: Your dad was obviously a big influence on you as well as a good father. How did your dad help shape you into the man that you’ve become?

PH: The biggest thing was his work ethic and his business ethic. You treat people properly. If you do something wrong you make it right. If you make a mistake or have a problem you fix it. That’s how you keep people coming back, you make it so they can trust you. And that’s how he was. Even if the mistake wasn’t our fault, if it was under our warranty we fixed it.

He supported us well. He did with less so we could race. He worked full-time in the wood logging business, and started this place part-time selling snow-mobiles. Then we opened full time in 1969 and it’s been going since then, first snowmobile repair and then we started selling Alouette snowmobiles. When they went out of business we sold Arctic Cat snowmobiles for a while. Then we sold Polaris snow-mobiles until around 2002. As you know we sold new BMW motorcycles, but we were too small of a dealer to keep selling them.

FP: Did you ever consider any other career?

PH: I went to mechanical engineering school, but this just took over.

Paul's custom-built Airhead off-road bike.

FP: Heid’s is a small family owned and run shop. What’s it like working with your mom and brother all day?

PH: It’s been so long that we’ve learned each others work patterns, you can almost anticipate what’s going to happen next. You still have family squabbles and what-not, but you have to get along if you’re going to last this long.

FP: I know you went to BMW motorcycle school. What was that experience like?

PH: Great. When I went to BMW school it was still in-house training, so they had very, very good technicians working with us. Craig Etzel was one of my teachers, and he was just super. He had a real you do it right work ethic, very much like my father. Details matter tremendously in this business. For example, we have people come in here all the time wanting services, and the first thing we do is check their tire pressures. You would not believe how so many riders let this simple thing go unchecked - blissfully unaware, to put it mildly.

FP: Even now some riders won’t ride anything but BMW airheads. Why do you think these old bikes still have such a strong and loyal following?

PH: For one they’re reliable as gravity. And two there’s the KISS principle -Keep It Simple, Stupid. It’s just a simple, by today’s standards, piece of equipment. Airheads are great - time marches on, yet they remain where they are. Other bikes have gotten better, but they are still that good. Take an early Slash 5. Find me another motorcycle from that era that you can still ride so many miles without having to do major work on. I consider the pre-Slash 5s as more collectible than ridable, but Slash 5s and on are such good, reliable motorcycles they can be considered ridable collectibles. They are just competent motorcycles that did everything well back then and they still do.

FP: How do BMW motorcycles stand up to other brands you’ve worked on?

PH: All brands of bikes have quirks and problems, no brand is exempt from that. Still, I believe if you look at the fit, finish, and quality of BMW motorcycles it’s still exceptional. Other companies have improved but I still believe BMW has an edge. All companies have gone to less maintenance, and maintenance is now easier for the technician like cartridge oil filters. Harley-Davidson is a perfect example. I hated working on the old iron-heads, but from the Evolution engines on everything is just so much better. It seems like it’s just easier for technicians to work on the modern bikes.

Paul's employees say he's a bit of a hooligan and never misses a chance to get the front wheel off the ground.

FP: You fixed my son’s Ducati by sourcing a neat, programmable ignition module from New Zealand, and you found the problem in the cold-start circuit on my Norton’s carb. How is it you can work on other brands so easily, when you’re not even trained on those brands?

PH: An engine is an engine. You have the same basic things required for every engine to run. Also, something we never used to have, there is now a plethora of information available on the Internet. It’s a great resource, you just have to sort through it carefully.

FP: How do you stay motivated to keep doing your best work?

PH: I just love motorcycles. I like nothing more than to get on one and I feel that my customers want the same thing. There’s nothing more frustrating than a mechanical device that just does not work properly.

FP: What is your opinion on new technology working its way into street bikes, like traction control and ride-by-wire?

PH: It’s the natural progression. Makes it more complicated, but makes a better beast. You have more potential for failure but systems in general have gotten more reliable. A good example is in snow-mobiles. They  could have had two-stroke direct-injection a long time ago, but were waiting for the processing power in the control electronics to improve enough. You have tremendous ability in small computers, might as well take advantage of it.

FP: What in your opinion is the most dependable motorcycle ever made?

PH: K bikes. I’ve seen more high mileage K bikes in here that require less work. Go look on eBay and see what a used K 100 engine costs. You can buy one for dirt because they don’t wear out. Compare that to a used R 100 engine which will cost you and arm and a leg. We have two used K bike engines here that we will probably never sell because they don’t ever break. Remember K bikes have the first generation of computer engine management which means the engines run right and are under a lot less stress. We’ve had other high mileage bikes come through here, like Gold Wings, but almost all of them have had something major done to them. We had a K 75 RT in here a few years ago that the guy never did anything to with 230K miles on it. It was ragged, it needed some love, but you turn the key and it started and you could have ridden it to California. The drive lines on the K bikes are bullet proof.

Paul's mother, Teri, and his brother Peter, who passed away in September 2016.

FP: Shaft drive is a hallmark of BMW motorcycles, yet many final drives have failed. What’s your take on this?

PH: Inadequate engineering testing over time, plus financial constraints. Then consider how often these bikes are over-loaded. How many riders even know what the GVWR (gross vehicle weight rating) of their motorcycle is? The K 1200 LT used the same final drive as the K 100. You never had “big mama and the picnic basket,” to use a phrase from one of my BMW school instructors, on a K 100. A lot of these bikes were just grossly overloaded. Perhaps the design of the final drive was at the outer limits of its capability. We’ve seen some that have gone 100K+ miles and never had a problem, while some fail at 20K. I think if, as the bikes got heavier and more powerful, the final drive design would have been beefed up accordingly, there wouldn’t have been as many problems. Real world function is very different from factory testing.

FP: If you had a direct line to BMW, what kind of motorcycle would you ask them to build?

PH: Simple. Keep innovating, like with the water-cooled twins, but keep it simple. I’d love an R 1200 GS that weights around 300 pounds, but I know it’s impossible. There’s a saying I like: “never trust a motorcycle you can’t look through.”

FP: What do you think of 200MPH bikes like the S1000RR being sold for street riding?

PH: Fantastic. However, the one thing we don’t  have in the US is tiered licensing, which is a mistake. In other countries you start out on a small motorcycle and work your way up. Responsible use of your throttle is the key. Just because you have it doesn’t mean you have to use it. And it’s up to us motorcyclists to police ourselves. I always tell kids coming in here they don’t want a crotch rocket to start with.

FP: What tips do you have for a dedicated owner who wants to work on his own motorcycle?

PH: Learn. Read. There is so much information available on any motorcycle, especially the older stuff. Find a buddy who has your bike and learn from their experiences.

FP: What’s the most fun you have on a motorcycle?

PH: Dirt roads on my custom dual sport. That’s how I started and what I alway go back to.

FP: If you could ride anywhere in the world, where would you choose?

PH: That’s a tough call, but the town of Johnsburg has a hundred miles of dirt roads so I’ll say right in my back yard.

FP: What are some of your other interests besides motorcycling?

PH: Hunting, fishing, hiking - basically anything outdoors - and listening to music, as well as being a volunteer fireman.

If you find yourself at Americade in Lake George, NY or in the Adirondack Mountains for any reason, be sure to visit Paul and the rest of the Heid family at Heid’s Hodaka and BMW, 2033 Garnet Lake Road in Johnsburg, NY.

A:

The process for bleeding brakes used to be relatively simple. Remove the master cylinder reservoir lid (carefully), protect any paint from splashed brake fluid, and then squeeze the brake lever (or depress the pedal) while a helper opens the bleeder valve on the caliper briefly. Repeat until clear brake fluid flows through the hose on the bleeder valve without any air bubbles present.

With the advent of ABS on motorcycles, followed by BMW’s infamous “whizzy” (servo-assisted) brakes, this doesn’t quite do the trick any more. This is a hydraulic-over-hydraulic system, and the brake fluid in each part of the circuit exists in two separate pools.

One pool goes from the input cylinder (master cylinder) reservoir on the handlebar (for the front brakes) or frame (for the rear brake) to the ABS control unit under the fuel tank. The other pool goes from the ABS control unit to the calipers. Flushing the system to put new fluid in it or simply bleeding the brake lines thus requires you to address both pools of fluid. (Which bike you have determines the total number of pools of fluid you have; for instance, the K 1200 LT bikes with these types of brakes generally have three pools, but depending on the year of manufacture, they could have four.)

Top view of an ABS control unit from an R 1150 RT. The battery is at the bottom of the photo and the bike’s Motronic computer is at the top. Note the combination of rubber and metal brake lines.

My guess—without having access to the R 1150 RT of course—is that Mike bled the system in the old-fashioned way, by opening the bleed valve on the caliper and squeezing the brake lever. Effectively what he did was empty fluid from the ABS unit-to-caliper pool, without replacing it because the fluid level in the “master cylinder” (on the handlebar for the front brakes or on the frame for the rear brake) reservoir would not have decreased.

To flush or bleed these systems, the following process may prove to be the most effective, but as always you should consult with a qualified BMW tech if you’re at all confused.

You’ll need:

• Catch basin for contaminated (old) brake fluid
• A big, unopened bottle (quart/liter) of fresh DOT 4 (or synthetic equivalent) brake fluid. This leaves you plenty of extra in case you make a mistake, spill some, etc. DO NOT use DOT 5 or silicone-based brake fluid.
• Combination wrenches suitable for your bleed valves on the calipers and the ABS control unit (sizes may vary)

Once you have access to the ABS control unit (you may have to remove body panels, seat, fuel tank, etc.), be sure to protect your frame and any other painted parts from spilled or splashed brake fluid – that stuff will take the paint right off. The system is under pressure, so fluid can spray out at high speed. Attach a hose or tube to the rear caliper bleed valve and run that hose to your catch basin.

The tall, capped fittings are the bleed valves for the ABS control unit. The short, angled, capped fittings (only one is visible) are for getting air out of the lines, but they are reversed from the fluid bleed valves – that is, the one that looks like it should be for the rear brake circuit is actually for the front brake circuit. It is very easy to forget this, which is why it’s advisable to go to a qualified tech if you get air in the system.

• Turn the key on.
• Remove the cap on the reservoir marked H (Hintere, or Rear) and top off the fluid in the ABS control unit reservoir if necessary. (see photo)
• Open the bleed valve a quarter turn.
• GENTLY apply the rear brake and allow fluid to drain, ensuring that fluid in the reservoir is always visible.
• Release the brake and close the bleed valve, then turn the key off.
• Top off the reservoir if necessary.
• Repeat above steps as necessary until you see clear fluid coming through the hose.

Put the wrench on the caliper bleed valve before affixing the hose to the catch basin. Alternately, you can use the open end, but doing it this way helps ensure you don’t over-tighten the bleed valve.

Using a funnel that screws into the ABS control unit reservoir can speed this process, as it gives you a good visual on when you need to add brake fluid. Beemer Boneyard sells them for about $35, or you can get the official BMW Motorrad tool, which is about $225 (p/n 83 30 0 402 174). The funnel also helps prevent air from getting into the system, which is important to both feel and function. A bent 7 mm combination wrench will also come in handy.

For the front calipers, the procedure is the same as the rear, making sure (of course) that you are filling the appropriate reservoir (V for Vorwärts or Forward) on the ABS control unit. Popular opinion says to start with the caliper at the end of the circuit, but if you’re doing both at the same time (and you should), it doesn’t matter which one you do first. Just be sure to only work on one caliper at a time, completing that one before moving on to the next.

Remember that brake fluid can and will damage the paint on your motorcycle. Always protect painted surfaces when working with brake fluid and clean up spills immediately. When you’re bleeding any part of the circuit, ensure the reservoir never runs dry, or you risk introducing air to the system.

Once you’ve flushed and bled both halves of the system from the ABS control unit, you’re only halfway done. Now you can move on to the fluid that starts at the brake lever or pedal.

Start at the rear again:

• Open the cap on the frame-mounted master cylinder reservoir.
• Connect the hose for your catch basin to the tall bleed valve on the ABS control unit.
• Top off the frame-mounted reservoir with clean, fresh DOT 4 brake fluid.
• Open the bleed valve a quarter turn.
• Press firmly on the brake pedal.
• While holding the pedal down, close the bleed valve.
• Release the pedal and refill fluid in the reservoir as necessary.
• Repeat these steps until clear fluid flows through the hose.

Once you’ve flushed and bled the rear, you can move to the front. Follow the same procedure for however many front calipers you have. If you somehow introduce air into the system, things get more complicated, and at that point, it’s advisable to seek professional help.

For hard-to-reach places, cleanup can be accomplished with spray brake cleaner, but always check the labels to make sure whatever cleaner you use won’t damage rubber, paint or plastic. Using lots of water may be a better cleanup solution. Use a drip tray to control run-off and help protect the environment.

The important thing to remember when dealing with the ABS control unit is that the brake fluid connected to the lever or pedal pushes on a piston inside the ABS control unit. The piston inside the control unit then pushes fluid to the caliper—two separate, distinct systems that work together to bring you quickly and safely to a full stop. The core of Mike’s problem was a simple misunderstanding of how the brake system on his bike manages fluid.

If you’re having a problem with your motorcycle that you’d like to see addressed, send your questions or issues to techquestions@bmwmoa.org, and we’ll address your problem in a future installment.

Q:

A:

The only tool you need to start testing is a digital volt-ohm meter (DVOM), also known as a voltmeter or multimeter. There are many on the market, but you don’t need anything special. Make sure it can read volts in direct current (DC) and resistance in ohms (Ω). The one I carry on my bike is a compact, auto-ranging multimeter made by Extech that cost about $40. There are many available on either side of that price point.

A digital volt-ohm meter, or multimeter, doesn’t need to be complicated or expensive. Having one small enough to carry on your bike as part of your regular tool kit could save you some hassle on the side of the road.

When you get that dreaded “click click click,” the first thing to check is your battery. Make sure the connections to the battery are tight and clean (free from corrosion). After determining the connections are good, break out your DVOM. Verify you’ve got the leads connected properly, then touch the red lead to the positive terminal of your battery and the black lead to the negative terminal.

Here, the positive terminal as on the far side of the battery, with the negative terminal at the bottom of the photo.

If the readout is above 12 volts, chances are your battery is good, and you can move on to the load test. If the readout is below 12, it’s time to hook your battery up to a trickle charger for a few hours (or better yet, overnight).

You can test the battery by putting the DVOM probes on both terminals or by going from the positive terminal of the battery to a known good ground point on the bike (in this case, a screw that touches the frame).

Once you determine the battery is carrying 12+ volts, then you can test the battery under load. You can eliminate the possibility of a bound-up starter giving you a false dead battery result by using the headlight. Put the headlight on the high beam setting, then turn the key to “On.” If the battery still reads above 12 volts, then move on to testing things out with the starter button.

Load testing by using the starter button is easier with a helper. Have one person hold the DVOM leads on the battery terminals, and with the bike’s ignition in the ON position, have the other person press the starter button (**BE SURE your bike is in NEUTRAL!**). No matter whether the bike starts or not, you should see a drop in the voltage readout. If the drop is minimal—a volt or two—your battery is okay. The amount of drop acceptable can vary and is dependent on your specific motorcycle; for instance, an older bike with points has a much lower threshold for acceptable voltage than a modern bike with an electronic ignition system.

With a modern bike, if the drop takes it much below 10 volts, you need a new battery. The problem there is that the battery is accepting a charge, but it’s just a surface charge. When a load is put to the battery—that is, when you try to start the motorcycle—the battery is not up to the task and has to be replaced.

Let’s say you’ve installed a brand-new battery and prepped it per the manufacturer’s instructions, but your bike still gives you the old “click click click.” The next step is to test the circuit’s continuity through the starter. BMW motorcycle starters carry the ground through the housing of the unit, so the number of wires going to your starter may vary. Find the main lug on the starter and verify the connection is clean and tight.

F, G and K bikes will have a starter with just one lug on it; make sure the connection is tight and free of debris and corrosion.

BMW motorcycles have two different starter setups – one for horizontally-opposed twins, and one for pretty much everything else. Horizontally-opposed twins have a starter with a built-in solenoid hanging right off the side of it—just like an automotive starter. Other bikes (F, G, K) have a two-piece setup; the starter is in one place, and the solenoid is in another place, probably under a body panel somewhere. These are a little easier to test, but only just a little.

Modern R bike starters are similar to automotive starters in that the starter and solenoid are built into a common chassis. These are a little harder to test, but not ridiculously so.

For the remainder of this article, let’s say your battery is putting out 12.5 volts. With the bike’s ignition off, touch one lead from your DVOM to the positive terminal on the battery and the other lead to the lug on the starter. This test will only tell you if your starter is absolutely dead; if the DVOM readout is 12.5 volts, then you know you’ve got continuity from the battery and through the starter to ground. If at this point the DVOM reads zero volts, there are a number of things that could be wrong, but it’s likely the problem lies within the starter itself. It could be as simple as corrosion between the starter chassis and the engine where it’s mounted, but it also could be that the brushes inside the starter have worn out. Either way and many ways in between, you likely need a new starter.

Testing the solenoid (or starter relay) is a logical next step. There should be two big lugs, and there may be some smaller ones or even a wiring connector. It’s the big, heavy-duty connection points you want to use for your testing. One will have a cable coming (more or less) from the battery; the other lug will have a cable going to the starter.

The ignition solenoid is a type of relay, and it functions much as relays do. At rest, there is no electrical connection between the contacts. When power is applied—in this case, by you pressing the starter button, which sends current to the “trigger” lug on the solenoid (one of the smaller wiring connections)—the contacts inside the solenoid come together, sending power from the battery to the starter.

Starter relay - open!

Starter relay - closed! This starter relay from an Airhead shows clear signs of corrosion and is indeed non-functional. In its resting state – that is, the starter button is not being pressed – its contacts are apart and no electricity flows through them. When the starter button gets pressed, electricity flows through the coil, turning it into a magnet. The magnet draws the upper arm down, making the contacts connect and flowing power from the battery to the starter.

One of the things that can go wrong with the solenoid is that the contacts simply degrade or corrode over time. They’re getting zapped with 12.5 volts several times a day, after all, and that can leave debris behind on the contacts, which can then get dirtier over time and stop making a solid connection. Testing the solenoid is simple. You can use either the positive or negative terminal from your battery; it doesn’t matter which. Put one probe on a battery terminal and put the other probe on one of the solenoid lugs, noting the readout. Then touch the probe to the other lug on the solenoid and note that voltage as well.

It may be hard to determine which lug on the starter connects to the battery and which to the starter, but you’ll know once you start testing it with your DVOM. It’s important to make sure the contacts are clean and tight. Corrosion such as seen in this photo should be carefully cleaned and the nuts retightened after cleaning.

You should get one readout at zero and one at 12.5 volts (or whatever your battery voltage is). If one of the readouts is anything other than zero or battery voltage, then it’s likely there’s a problem with your solenoid. If both solenoid lugs test the same, whether it’s at zero or 12.5 volts, the problem is likely the wiring between the battery and the solenoid, and that could include the connections at either end. You can also test from the solenoid to the starter. Put one DVOM probe on the lug connecting the solenoid to the battery, and the other on the starter lug. If you get anything other than battery voltage (12.5V in the example here), then there’s a problem between the solenoid and the starter. As a backup, test from the other lug on the solenoid to the starter – you should get zero volts.

One of the frustrating aspects of chasing problems like this is that everything can test out okay, but your bike still won’t start because there’s some minute problem inside the starter that looks fine when you’re using a DVOM, but fails when you actually put the full load of the battery to the starter. Clearances are tight, and if things are degraded even a little bit, it can prevent the starter from functioning properly. If you’ve seen anybody bang the starter on their car or truck with a hammer and the thing magically starts after that, then you’ve experienced what can temporarily “fix” a stuck solenoid. If you’ve seen somebody rock their can back and forth in gear to get it to start, you’ve seen what a dead spot in the starter’s brushes can do.

Between the battery, the solenoid, the starter and all the wiring connecting those three components together, there are a lot of things that can go wrong. Luckily, it’s relatively easy to use a digital volt-ohm meter to test the basics of the circuit, and that could point you right to the likely problem.

If you’re having a problem with your motorcycle that you’d like me to address, send your questions or issues to techquestions@bmwmoa.org, and we’ll address your problem in a future issue. Next time I’ll discuss how BMW’s integral brakes function and go over why bleeding the brakes on a bike so equipped is a little more involved than it looks.

Set your DVOM to Volts DC (VDC) and use this handy reference chart.