Let's Ride Page 12
I’m going to start at the front of the bike and work my way back. The most complicated system (and thus most prone to failure) is the fork. A fork is probably the most likely item to get tweaked in a crash, since it is at the front of the bike and the first thing that connects with whatever a rider might be crashing into. It is also prone to less serious problems, like worn-out seals.
The majority of motorcycles you will be looking at will use hydraulically damped telescopic forks. These are the two long shock absorbers connecting your front wheel to your handlebar. There are other types of front ends—Harley uses an old-fashioned springer-type fork on some models, and BMW has too many oddball systems to keep track of—but I’m going to focus on the hydraulic front fork, which is the most common type.
The fork assembly is held together by metal pieces called “triple clamps.” These attach the fork to the steering head, which is the tubular assembly on the front of the frame in which the fork pivots. The triple clamps hold either the fork tubes or the fork sliders, depending on what type is used. Think of the fork tube as the male part of the fork, the part that inserts into the female part, and the slider as the female part that gets penetrated by the male part. (This may seem crude, but these are the terms that mechanics have always used.)
Traditionally the male part is at the top and the female part is at the bottom, but I’ve noticed that in recent years the trend has been to reverse these positions. Consequently, the inserting male part is now often found at the bottom, down by the wheel, and the female part is up by the triple clamps. These were originally called “upside-down forks,” and are still often referred to as “USD forks,” though they are becoming so common that more often than not people just call them “forks.” At first USD forks were only found on sport bikes, but now they’ve begun to appear on all types of bikes, including cruisers. Harley uses USD forks on its new Sportster XR1200 and Victory uses them on its Hammer and Kingpin models.
The first tools you’ll need to check a bike’s fork are your eyeballs. Look at the fork from the side. The two legs of the fork should line up perfectly. If one of the legs is skewed at a bit of an angle or looks bent, chances are the bike has experienced more than the normal amount of wear and tear. If the whole assembly looks a little cockeyed, then either the triple clamps are bent or the frame itself is bent in such a way that the steering head itself is tweaked. In the grand scheme of things, these problems range from really bad to downright terrible, and they should motivate you to find a different bike.
The other thing to look for in the visual inspection is oil leaking from a fork seal. If the fork hasn’t been cleaned, you’ll easily be able to see a ring where oil has collected and grime has built up around the fork tube, right at the end of the fork slider’s travel (the point at which the male part is most deeply inserted into the female part). Even if you don’t see this telltale ring, the fork seals may leak; the owner may just have wiped the tubes down so the leak wasn’t obvious.
You can tell if this is the case with a simple test. First, make certain that the owner or the mechanic you brought along, or anyone else capable of standing on his or her own two feet, is standing beside the bike to help keep it secure. Go to the front of the bike and get a strong grip on the handlebar. With the front wheel placed firmly between your legs, squeeze the front brake lever to keep the bike from rolling away from you (or worse yet, over you) and lift the bike up off its side stand. Once you have the bike securely upright, pump the fork up and down a few times. When you are finished, put the bike back down on its side stand, making sure that it’s resting in a secure position, and rub your finger along the exposed part of the fork tube above (or below on USD forks) the slider. If the seal is leaking, you’ll feel a thin film of oil.
If the bike is more than a few years old and hasn’t had the fork seals replaced, there’s a good chance you’ll find a leaky fork seal. A leaky fork seal shouldn’t be a deal breaker, but like just about everything else associated with a motorcycle, it will be relatively expensive to fix. Call a motorcycle shop that sells the model you’re looking at and get a quote for replacing the seals. Your final offer for the bike should reflect the money you’ll have to pay to repair the fork.
Follow the same procedure to check for other possible fork problems. When you’re pumping the fork up and down, make certain that both sides of the fork legs are moving up and down freely, without binding or making noise, both of which could be signs of expensive problems to come.
Steering Head Bearings
You can check the steering head bearings at the same time you’re checking out the fork. While you’re holding the bike up turn the handlebar all the way to the left, then all the way back to the right. Listen to see if you hear a clunking sound, which could indicate that a steering head bearing is loose or worn out; it may have dents and flat spots that can’t be adjusted away.
If the bike has a center stand, put it up on the center stand, as described in chapter 3.
Once the bike is securely on the stand, have the person who’s with you place his or her weight on the rear of the bike. This should lift the front tire in the air. When you’ve made sure the bike is secure, center the bar so that the tire is facing straight ahead and let it fall to one side, and then the other. If the wheel moves evenly and smoothly, chances are it’s in good condition. If it moves with a clunky, jerky motion, the bike likely has problems with the steering head bearings.
Again, this is not uncommon on older bikes, and it shouldn’t be a deal breaker; the bearings may just need an adjustment, but there is a good chance that they will need to be replaced. This will be even more expensive than leaky fork seals, especially if the bike has a lot of bodywork that needs to be removed. Check with a local shop to find out what this will cost to repair, and if you decide to buy the bike, make an offer that will reflect that cost.
While you have the front of the bike up in the air, check the condition of the wheel bearings by grasping the front wheel at a right angle to the fork and rock it from side to side. If you notice any play in the wheel, the wheel bearing will need shimming or replacement.
Tires
If you’re used to automobile tires, which often last fifty thousand miles or more, you’re in for a rude and expensive awakening when it comes to motorcycle tires. The very best motorcycle tires won’t last ten thousand miles; in most cases you’ll be doing good to get seventy-five hundred miles from a set of tires. And these tires are expensive; on big touring bikes like the Gold Wing or Vision that require the removal of a lot of plastic bodywork to gain access to the tires, you could be looking at $600-plus to buy a set of high-quality tires, and another $300 to have a shop mount them.
There’s really no way around this—it’s just the price you’ll pay to ride a motorcycle—but with that said, you can still do a few things to help keep your costs down, even when you first buy a bike. Pick up a tread-measuring tool and measure the depth of the tread on any bike you’re thinking of buying. Make sure the tires have at least 50 percent of their tread life left. If they don’t, get an estimate for the cost of tire replacement from your local shop and reflect those costs in any offer you might make for the bike.
Check the air pressure of the tires. Low air pressure is obviously not a major problem, but you’ll want to make certain that the tires are properly inflated before a bike is safe to take out on a test ride (consult the owner’s manual for the proper air-pressure level). Low pressure can mean a tire has a leak, but as often as not it just means the bike might have sat unused for a while. If a bike has been unused for more than a few months, check the sidewalls for dry rot, cracks, and weather checking. If a tire shows signs of problems like this, it should be replaced regardless of how much tread is left on it.
You can get a lot of information from the tire itself, like the date the tire was manufactured, for example. The date of manufacture is found in the final four-digit code stamped into the small oval area on the tire’s sidewall, right after the word DOT
(Department of Transportation). The first two digits denote the week of the year in which the tire was manufactured and the last two digits represent the last two numbers of the year of manufacture. For example, if a tire was manufactured in June of 2006, the code will read: “2806.”
If the tire has a code that ends in three digits, that means the tire was manufactured before the year 2000. If that’s the case, then figure that you will need to replace it regardless of how good it looks. There is no hard-and-fast rule about how old a tire should get before replacing, but if you don’t have the sense not to ride on tires that are over ten years old, you should probably take up a safer hobby, like knitting. Even if a tire is just six or seven years old, you can assume it’s past its prime and will need replacement before you start riding the bike. Again, this isn’t a deal breaker, but when negotiating to buy the bike, your offer should reflect the cost of tire replacement.
Frames
Modern motorcycle frames are generally pretty robust pieces of equipment and won’t shake to pieces the way they used to on earlier bikes. (There are, however, exceptions, including Suzuki’s first-generation TL1000, a high-performance V-twin sport bike built in the late 1990s and early 2000s, and which developed a notable reputation for frame failure. Most frames you look at will either be made of tubular steel or aluminum alloy beams, though those found on BMWs from the 1980s and 1990s are virtually not frames at all, but rather consist of a couple of subframes bolted to the engine cases. In general, these were strong and reliable and should be no more problematic than the frames on other modern bikes.
Even though frame failures are rare, you should still take some time to inspect the frame of any used bike you consider buying. Check the gussets and welds for cracks, especially in high-stress areas like around the steering head. Look for dents or severe scratches that might indicate a bike has been wrecked, and look for signs of corrosion around the battery box. Take note of flaking paint, which could also be a sign that a bike has been through a serious crash. Don’t walk away from a bike because of a little flaking in the frame’s paint, but if you do see this, keep your eyes open for other trouble signs.
Swingarms/Rear Suspensions
All modern motorcycles have some sort of swinging arm rear suspension. From the 1950s until the 1980s this consisted of a fairly standard setup, with a metal fork attached to the rear wheel, coming together in front of the wheel, and attaching to the frame at a pivot point behind the transmission. A pair of shocks, one on either side of the rear wheel, controlled the wheel’s up-and-down motion.
This status quo began to change in the mid-1970s. Yamaha used the first modern single-shock setup on its factory motocross race bike in 1973. Within a few years both Yamaha and Suzuki offered single-shock dirt bikes to the general public. At first these used triangular swingarms that placed the shock at the top of the triangle, in front of the rear tire. The shocks on these bikes rested at an angle and connected to the frame up under the gas tank. This system was soon replaced by a setup that placed the shock upright in front of the wheel. By the early 1980s all competitive dirt bikes used this latter setup.
At the same time, single-shock arrangements began to appear on street bikes. In 1980 BMW introduced the R80G/S, an 800-cc dual sport that featured a single shock, though this was mounted in the traditional position, alongside the rear wheel. Where the BMW design broke with tradition was its use of a single-sided rear swingarm, which was basically like a traditional swingarm cut in half. BMW called this system the “Monolever.”
Yamaha used a more innovative single-shock system when it introduced the Virago series in 1981. These early Yamahas used a system much like the very first single-shock dirt bikes, with a triangular swingarm and a laid-down shock that ran under the seat and connected to the frame up by the gas tank.
Over the next few years Japanese sport bikes began to feature single-shock rear suspensions, though these followed the practice of the later dirt bikes, with a vertical shock mounted in front of the rear tire. Harley even got into the alternative rear suspension business with its Softail system. Like the Virago, this system featured a triangular rear swingarm, but instead of being located under the seat, the shocks were mounted down under the engine, hidden from sight.
The main difference between the Harley system and the various systems used by the Japanese and Germans was that the Japanese and German systems were all about function. The main purpose of the Harley system was cosmetic; Harley was trying to re-create the look of the earlier hardtails (bikes without any rear suspension at all). It did this by hiding the entire rear suspension system as best it could.
Today we have a bewildering variety of rear suspension designs to pick from. Having said all this, unless you’re planning to spend a lot of time on a racetrack, you should simply make sure that any used bike you’re buying doesn’t have problems with its swingarm. Swingarms generally are extremely stout and should cause little trouble over the life of a motorcycle, but you’ll still need to check for potential problems.
First, examine the shock or shocks. Make sure they aren’t leaking fluid, or that they haven’t lost their gas charge if they are nitrogen shocks. You can check for leaks in much the same way you check the fork seals—bounce the bike up and down and then check for greasy moisture on the shaft of the shock. You should be able to tell if the shocks are properly charged and/or filled with fluid after you bounce the bike up and down. If it bounces too easily, the shock(s) will probably need work. This is not uncommon on bikes with a few miles under their belts, but like everything else, it will be expensive.
An even more expensive repair would be to replace the swingarm pivot bushings. When these get bad, they can make your rear wheel wobble while you ride down the road. As you might imagine, this can have fatal consequences on the highway and needs to be fixed immediately. Thankfully you should easily be able to determine if the swingarm bushings are bad before your bike enters a “death wobble” on the open road. The procedure for checking swingarm bushings is similar to checking the steering head bearing and is much easier to do on a bike equipped with a center stand. When the bike is on a center stand, the rear wheel is lifted up in the air so you can wiggle it back and forth to see if there is any play in the bushings. If there is a little play, that might not mean there’s a problem—on many bikes the swingarm pivot simply can be adjusted to eliminate this play—but if the swingarm clunks from side to side, you can be certain the bike will soon experience expensive and dangerous problems. Walk away from any bike with a sick swingarm while you still can.
The Final Drive
This is also the time to check the final drive system. As mentioned in chapter 1, there are three common types of final drive systems: chains, shafts, and belts. Belts are the best system, in my opinion, and require little maintenance, but they can fail with age and wear. For this reason, check the condition of the rubber to ensure it’s not cracked or coming apart. Most important, make certain the belt has all of its teeth. If teeth are missing from the belt, it is just about to fail.
A damaged belt is not a huge problem on some belt-drive bikes, but, on others, it could get expensive. Generally speaking, if the belt runs inside the frame as it passes over the swingarm pivot between the front and rear pulleys, as it does on Harley-Davidson touring bikes and Softail models, the frame will have to come apart to replace the belt. This is a huge job and is much more expensive than changing belts on models that have the belt running outside the frame, such as Harley’s Dyna and Sportster models. If the belt has any damage or noticeable wear, check with a local shop to see how much they charge for replacing belts on that model. If you decide to buy the bike, reflect the cost of belt replacement in your offer.
I prefer belts over shafts because belts don’t alter the handling characteristics of a bike the way shafts do, even though shafts require less maintenance than belts. When you have a shaft-driven bike up on a center stand (most bikes with shaft drives have center stands), you can check the oil level i
n the rear drive unit by opening a screw-in plug that rests on the upper part of the ring and pinion housing and looking inside to see that the oil is at the proper level. Once you’ve determined that it is, put the bike in gear (with the engine off, of course), grab the rear wheel, and jerk it back and forth. If you feel a loud, loose “clunk” inside the rear drive housing, the bike may be about to experience a very expensive drive-shaft failure.
Chains are the most common types of rear-drive systems, and they also wear out the fastest. In the 1970s and early 1980s a few manufacturers like Harley-Davidson and Yamaha used chain-drive systems that ran the chain in an enclosed oil bath. These enclosed chains lasted virtually forever, but the cases that held the oil were heavy and prone to leaking. They eventually proved to be a technological dead end and by the mid-1980s all motorcycle companies had abandoned the idea and gone back to open chains and sprockets, or in Harley’s case, belts.
You’d be lucky to get twenty thousand miles from a chain and a set of sprockets. If you’re like me, that won’t get you through one riding season. Add to that the fact that the chain final drive is the most maintenance-intensive system on a modern motorcycle, and you can see why I don’t care for them. You’ll need to adjust your chain at least every week, perhaps every other day if you’re a serious rider.
Be prepared to get dirty when checking the condition of the chain. Although there are some good chain lubricants that don’t leave a greasy buildup or attract too much road grime, even the cleanest chain on a bike that is regularly ridden will be somewhat greasy and dirty. This is where the clean rag you brought along will come in handy.
First check the tension on the chain to make certain the chain isn’t so loose that it will cause problems when riding. If the bike is well maintained, then the slack should be within the manufacturer’s tolerance, usually meaning the chain should have enough free play to move up and down an inch or two. An overly tight chain might be evidence of a well-meaning but ill-informed seller. A slightly loose chain may only mean the bike gets ridden a lot, but in my mind, a chain that is sloppy is a red flag indicating its owner neglects basic maintenance. If the chain is too loose to ride safely, have the owner adjust it before going out on a test ride.