Subject: rec.motorcycles FAQ of 93.10.01 (Part 1 of 6) This is the rec.motorcycles Frequently Asked Questions list. It will be posted near the first of each month. Please send requests or submissions to [email protected]. (DoD #978, KotF) Items marked with an asterisk (*) are new or changed from the previous FAQ. *** Terminology: Q: I've seen some unfamiliar terms while reading the newsgroup. What do they mean? A: You think maybe we can read your mind? Well, here are a few commonly-used terms: cager motorist inside a car or pickup Denizens the kind of people your mother warned you about DoD I'd tell you, but then I'd have to kill you The DoD FAQ appears in rec.moto at the beginning of each month. endo what happens when you get too exuberant with a stoppie. FOAF story "friend of a friend" story - usually bogus highside falling over to the outside of a turn (bad) lowside falling over to the inside of a turn (ditto) [email protected] (H. Marc Lewis) adds: "You don't have to be turning to highside (or lowside). If the bike is leaning to one side (turning, tankslapper, whatever) and you fall off on the same side, then it's a lowside. If the bike violently flips you over center to the other side (and beyond!) then it's a highside. I've seen and done both during 7 years of desert racing. The highside is by far the worst of the two..." MSF Motorcycle Safety Foundation. They teach 'How to Ride' schools, mandatory in some states. spooge any semiliquid nasty substance squid someone who rides far outside his abilities, often to the detriment of himself and his equipment. stoppie a maximum-effort stop where the rear wheel is lifted clear of the pavement. WFO Wide F***ing Open - the normal throttle position for Denizens, squids, and unfortunates on 50cc Honda step-throughs. ===================== Q: Who the hell is Lance Holst, and why is he a jerk? A: That's for us to know and you to find out. ===================== Q: Why doesn't the rec.motorcycle FAQ come out on the first of the month like most other FAQs? A: We use the Mayan calendar. *** Riding: Q: I've never ridden before, and I'd like to take a course. Where can I find one? A: In the USA, the Motorcycle Safety Foundation has courses several times a year. To find the next/nearest course, call 800-447-4700. Some states may also have their own required courses. Check with your local DMV. ===================== Q: I've never owned a motorcycle before, but I'd like to buy one. What's a good first bike? A: Don't let your hormones get the upper hand. Start small. Try to find something short enough that you can touch the ground with both feet when at rest. Experienced riders don't care, but it's very comforting when you start out. Try to find an older, used machine. It doesn't have to be perfect as long as it's safe. Registration and (particularly!) insurance are cheaper on older or smaller bikes. If you drop it, you won't feel nearly as bad as you would if it was a new ZZX700RRR or whatever. Once you have some miles racked up, you'll be a lot better at deciding what kind of machine you want to buy. You can sell the old one, trade it in, or keep it for a spare. ===================== Q: When I go around corners, should I lean my head with my body or keep it perpendicular to the road? A: Lots of people ride either way. At low speeds it probably doesn't matter. The fastest racers keep their head level no matter which way they're leaning. Keith Code's Superbike school also recommends this. ===================== Q: What's proper behavior for a passenger riding pillion? A: [email protected] writes: Here's what I tell passengers: - Don't think or worry about leaning. Instead... - Sit close and hug me tight. That way we are essentially a single unit---and I control the lean for the both of us. [It's particularly important when carrying a large male; if he's sitting back it's like a large weight at the end of a spring sticking up from the rear of the bike, which makes it wobbly and hard to control. I explain this to guys to get them over the macho, guys- can't-hug-guys thing. I explain this to women also: since women tend to be lighter and have a low center of gravity, when a small- to-medium woman sits close & hugs tight, I find almost no noticeable effect on handling (though there *is* a noticeable effect on my mood :) ] - Ignore the things that look like handgrips beside the saddle. - If you really want to participate, shift your head to look over my inside shoulder in turns---shifting the ~25 pounds of head+ helmet gives plenty of contribution to the lean. Otherwise don't worry about it, just pick a shoulder and stick with it, switch when you get bored. - Keep your feet on the pegs at all times! Don't put them down when we stop at a light or anywhere else---I don't want them to get mangled when I start moving. - You may want to stand up on your pegs a little when we stop, to keep from sliding forward on the seat. - Let me know if you're uncomfortable with freeway speeds or extreme leans or lane-splitting or whatever. [I try to not to terrify newbies.] - Open or close your faceshield as makes you happy. - Enjoy! The above works for me, riding a standard-style street bike ('83 Nighthawk 650). I imagine things might be different for sport or touring bikes. [comment: Looks quite complete. Probably the most important thing is not to get a case of the red ass when hauling a newbie - it can be scary as hell back there. Also be wary when carrying experienced riders, as they may shift their weight to "help" you without thinking about it.] ===================== Q: What is lane splitting, and why would I want to do it? A: Lane splitting is when you ride between the lanes of traffic. This is legal in some states, not forbidden in others, and illegal in still others. It can be an enormous time-saver when the freeway turns into a parking lot at quitting time. Some people - including some motorcycle magazine editors - advocate lane splitting and have done so for years. Others, thinking of how erratic the average cager is already, prefer not to take the chance of being creamed when someone changes lanes or opens a door to dump a spittoon. Some people make a distinction between lane splitting and lane sharing. The same comments apply. ===================== Q: I'd like to ride along with several friends, but I'm afraid we'll get tangled up or run into each other. Are there any rules for riding in groups? A: There aren't any formal rules. Some states permit riding side by side, other states require you ride staggered. Unless you're very familiar with who you're riding with it's a good idea to ride staggered. In most states, groups must stop individually for stop signs or red lights. It's bad practice to ride through a red light even if you're in the middle of 200 riders. Large group rides sometimes have police escort; if so, follow police signals. Sometimes it's hard to differentiate "blow through this red light" from "there's a wasp up my sleeve." Generally, when riding parallel, the bike nearest the shoulder has right-of-way. It's assumed that the inside bike can crowd the divider and any oncoming traffic, while the outside bike may be facing a ditch or stepped shoulder. When riding staggered, the bike in front normally has the right-of- way. You can see the guy in front just fine; he has to use his mirrors to see you. By assuming you can take care of yourself, he doesn't have to worry about collision if he has to dodge a pothole or armadillo. Remember, when you're riding in a group, you only have *half* a lane. Worn pavement or crosswinds can make it difficult to keep your mirrors or bodywork out of someone else's space. (continued) Subject: rec.motorcycles FAQ of 93.10.01 (Part 2 of 6) ===================== Q: What is countersteering, and why would I want to do it? A: That's a complex subject. Ed Green ([email protected]) has submitted a mini-FAQ on the subject: How do motorcycles turn? by Ed Green, a recognized non-expert in the field A frequent topic of discussion, and the source of much confusion, on rec.motorcycles concerns the mechanics, and underlying physics, of how motorcycles turn. It would seem that such a basic maneuver should be well understood by all motorcyclists. Surprisingly, many experienced riders have no idea how they turn, they probably never think about it. Many others have very definite ideas about how they turn, which are likely incorrect. Even among the elite and erudite Denizens, there is considerable disagreement as to the mechanics involved with both leaning a motorcycle, and actually turning one. Outlined here are the four major theories of motorcycle turning which came out of a recent flame war, er, discussion, on the subject (hopefully presented somewhat objectively). To begin with, motorcycles, at greater than parking lot speeds, must lean to turn. This is part of why they are so fun to ride. The four predominate theories of turning are evenly divided between leaning and turning, thusly: 1. Leaning (including countersteering) 1.1 Gyroscopic Precession 1.2 Steering-induced Roll 2. Turning 2.1 Camber Thrust 2.2 Steering Geometry 1. Leaning Many people assume one leans a motorcycle by shifting body weight. While it is possible to induce lean in this manner, the quickest, easiest, and most controllable method of leaning a motorcycle is by counter-steering. Counter-steering is a technique whereby the rider exerts pressure on the *inside* handlebar (left for a left- hand turn, right for a right-hand turn), to lean the motorcycle in the desired direction. This is in effect steering the motorcycle the "wrong" way, from the point of view of operating a tricycle, thus the term "counter-steering." THAT it works is undeniable, and can be proven easily with a short ride. Both the rate of transitioning to the lean (how quickly the bike leans) and the degree of the lean (how far over it leans) can be controlled by the rate and degree of pressure applied to the grip. HOW counter-steering works is debatable. The two leading theories are gyroscopic precession and steering-induced roll. 1.1 Gyroscopic Precession When riding at any appreciable speed, both wheels of the motorcycle exhibit the properties of a gyroscope. This contributes to the stability of a moving motorcycle. One such property, called gyroscopic precession, is that when a lateral force is applied to the axis of a free spinning gyroscope, the axis moves in a direction 90 degrees from the applied force, in the direction of the spin. For a motorcycle front wheel, this means that a force applied which attempts to move the axis on one side of the wheel back, toward the rear of the bike, will result in an effort by that axis to move up. Similarly, a force applied to move the hub forward results in a force trying to push it down. Thus to execute, say, a right hand turn, the rider pushes on the right grip, seemingly to steer the front wheel to the left. The forks translate this input to hub of the wheel as a force pushing forward on the right side of the wheel, and backward on the left side. Gyroscopic precession will generate a force directed down on the right side, and up on the left, which forces the bike to lean to the right. This gyroscopic business can most easily be demonstrated with a bicycle. Position the bike in such a way that the front tire is in the air and can rotate freely, and spin it up to a good speed. Holding the handlebars, attempt to turn the wheel to the left, by pushing on the right grip, and pulling on the left. You will feel the wheel trying to push the whole assembly over to the right. 1.2 Steering-induced Roll The point of contact between the motorcycle and the road is called the contact patch, and is that small area of the front and rear tire beneath the hubs (on level ground) which is resting on the road surface. All actions which depend on frictional forces between the tires and the road (such as acceleration, braking, and cornering) depend on this contact patch, and the contact patch is the point of application of the frictional forces. As long as one accepts that the center of mass of the motorcycle+ rider system is somewhere above this contact patch, then any frictional force which displaces the tires to the side acts at the point of contact with the road, and will induce a pivot about the center of mass (with a moment arm of the distance from the contact patch to the center of mass). This pivot about the longitudinal axis of the motorcycle is what is referred to in aviation as roll (when one wing of the plane is higher than the other). This steering-induced roll is much easier to visualize than gyroscopic forces, and is most simply described as "steering the wheels out from under the bike, to make it lean the other way." 2. Turning Through one or the other of these techniques, or some combination of the two, the motorcycle is leaned over by counter-steering. The motorcycle can also be leaned through weight shift, in which case neither of the above theories hold. That is only half the answer, however. Once the motorcycle is leaned, what makes it turn? Assuming for a moment it doesn't just fall over, why shouldn't it continue leaned over in a straight line until it runs out of gas? The good folks of rec.motorcycles have been hard at work on that one, too. The two leading theories for cornering of a leaned-over bike are camber thrust and steering geometry. 2.1 Camber Thrust Unlike the tires for cages and bulldozers, motorcycle tires have a round profile. The diameter of the tire changes from a maximum at the center (the contact patch if going straight), decreasing to a minimum at the rim. When the bike (and thus the tire) are leaned over, during a single revolution of the wheel, the center portion of the tire must travel further than the part near the edge. This induces what is called camber thrust, and it forces the tire to trace out an arc in the direction of the smaller diameter. Camber thrust can be demonstrated by placing an empty ice cream cone on its side, on a flat surface, and giving it a push. The cone will not roll in the direction it was pushed, but will constantly turn from that path, toward the smaller end. 2.2 Steering Geometry The steering stem and handlebars of a motorcycle are not positioned directly above the hub of the front wheel, but are angled back to varying degrees, referred to as rake. Thus, the weight of the motorcycle+rider is supported by the front wheel, not straight up and down, but at an angle which points through to a point ahead of the contact patch. The distance from that point to the actual contact patch is called trail. During straight-up and straight-ahead riding, this has no effect on steering, because the force is transmitted along the center axis of the motorcycle, which is the same as the center axis of the front wheel. When leaned over, however, this configuration causes a force to be applied to the rear part of the front tire, causing it to lift, turning the wheel into the curve. The motorcycle then naturally follows the front wheel. This view of turning is essentially the same as that for other vehicles, using lean only to counter the centripetal acceleration caused by the bike's linear momentum. This aspect of steering geometry can be demonstrated by holding a bicycle (or motorcycle) upright, with the handlebars and front tire free to move. Lean the bike to the right, and the front tire will "fall" (actually, be pushed by the steering geometry) to the right, and similarly for a lean to the left. Thus, the lean of the motorcycle, even if initiated by a countersteer, forces the front tire to point to the inside of the curve, carving out a turn, and the lean also balances the centripetal force which would otherwise push the bike over to the outside of the turn. So, in summary, a motorcycle must lean to turn. The quickest way to lean a motorcycle is to use counter-steering. Counter- steering leans the motorcycle through some combination of gyroscopic precession and steering-induced roll. Once leaned over, the motorcycle turns by some combination of camber thrust and steering geometry. What is the exact combination of each of these effects in actually causing leaning and turning? Pick two, three, or all four of them, come up with your own mix, go find a biker, and argue about it. *** Mechanical: Q: I pulled a wheelie the other day. Now my steering has a "catch" in it, the the bike wants to veer to the side. A: You probably notched the steering head bearings. Under a side load (like whopping the front wheel back on the ground) the races can get dented, balls flattened, or both. The only fix is to replace the bearings. Taper rollers are much less susceptible to this sort of damage, and conversion kits are sometimes available. ===================== Q: My 1978 Suzuki GS750 is supposed to use grade SE oil. All I can find is SG. Will it work? What about special motorcycle oils like Golden Spectro? A: The SE and SG are Service Ratings. SE has been superceded by SG, which is generally a superior grade of oil. There should be no troubles running SG. The vendors of the specialty motorcycle oils claim their oils are better than ordinary automotive oils. That could possibly be true, particularly with regard to motorcycles using roller bearing cranks. In most cases special motorcycle oils are probably a waste of money. Some motorcycles never seem to shift right, usually because they have clutches that run in oil and automotive oil doesn't always let them properly disengage. Various rec.moto participants have reported greatly improved shifting and clutch action with special motorcycle oils. Even expensive oil is cheaper than a clutch or transmission. Ed Hackett maintains a detailed FAQ on oil. You can annoy him at [email protected]. (continued) Subject: rec.motorcycles FAQ of 93.10.01 (Part 3 of 6) ===================== Q: Can I use a synthetic oil in my motorcycle's engine? A: Motorcycles in general tend to be highly stressed, run hot, are abused when ridden, and tend to be stored for extended periods. These are virtually tailor-made circumstances where synthetic oils can shine. Unfortunately, most modern motorcycles use a "wet" clutch, that is, the clutch runs in oil. (despite how wacko this sounds, it's true) Some synthetics can cause your clutch to slip. If you have a wet clutch and really want to try synthetic oil, give it a try. If your clutch slips you can always drain it and put regular oil back in. ===================== Q: I've been looking to buy a [brand and model name not important]. Several people have told me those bikes have troubles with second gear. How can I tell if this one is OK, and why do they have this problem? A: Second gear problems are the most common of all. They tend to be worse on high-power machines. Typically, the rider doesn't get the gear all the way into engagement, and it pops out under hard acceleration. This typically rips metal off the engagement surfaces, making it that much easier to pop out the next time. Eventually the machine will pop out of gear under acceleration. Incorrectly adjusted clutches, careless shifting, and shifting without the clutch can all cause second gear problems. The fact that you could shift your dirt bike without the clutch is not relevant; your dirt bike probably doesn't weigh 550 pounds, run on pavement, and have a fat tire on the back. ===================== Q: My motorcycle seems to use up chains pretty fast. How can I tell the difference between a good chain and junk chain? A: I wrote an article for Australian Motorcycle News which covered this subject in detail. I've reproduced it here: Years ago chains were considered disposable items. I remember scraping up money for the spring chain and sprocket ritual every year when I was in high school. Sometimes the chain wouldn't make it through the summer, even with fanatic oiling. Every T-shirt I owned had an oil stripe down the back on the left, much to my mother's dissatisfaction. I once had a two-month-old chain on my 175 Kawasaki snap while going 50mph. The broken chain wrapped itself around the swingarm and locked the rear wheel solid, whereupon the rear wheel decided it would lead for a while. By some miracle I came to a halt still vertical, but I have had a paranoid distrust of chain drive ever since. Now what, might you ask, would cause a chain to break like that? It was properly lubricated, adjusted, and running on the correct size (new) sprockets. Chances are that the local motorcycle shop had sold me some ordinary industrial chain instead of motorcycle chain. Such unscrupulous dealings were far more common years ago than they are now. A real chain might cost $30 then, but farm machinery chain sold for a little over a dollar a foot. What's the difference? In its simplest form, the roller chain consists of side plates, pins, and rollers. When properly lubricated, this type of chain will perform acceptably for most engineering purposes. Unfortunately, proper lubrication consists of an oil fog or bath and freedom from dirt, both conditions unlikely on a motorcycle. Twenty years ago some machines still came with enclosed chains, but the enclosed chain died away not because of styling, but because it was a tearing pain in the arse to service the chain or rear wheel with the bulky (and oftimes leaky) enclosure in the way. The oilite-bushed chain assisted the enclosed chain to oblivion. A porous bushing was pressed into the roller and rode on the pin. This porous bushing was impregnated with lubricant and would absorb chain lube too. With a moderate amount of maintenance the bushed chain was satisfactory if not perfect. Since the mid-1960s all "real" motorcycle chain has been of the bushed type. The chain that caused my hair-raising ride was likely of the previous type. In the mid-1970s the "O-ring" chains came into use. These were bushed chains using O-ring seals to keep the lubricant in and dirt and water out. They represent the latest word in drive chain design, being reliable, long lasting, and low-maintenance. Indeed, when run on plastic sprockets, the O-ring chain may need no other lubrication during its operational lifetime. Modern motorcycle chains come in two basic types - those which are endless, and those which use master links. Endless chains came about when engineers realized that most catastrophic chain failures ocurred at the master link. By eliminating the master link, reliability could be enhanced. Unfortunately, endless chains can cause a problem if the sprocket sizes have been changed much; if it is too long or too short, nothing can be done. Endless chains also usually require time-consuming removal of the swingarm for replacement. Motorcycle drive chain contains two kinds of links. Roller links consist of two side plates, two rollers, and two bushings, all a slip fit over the drive pins. Pin links consist of two side plates and two drive pins, with the pins being a tight press fit into the side plates and staked in place for permanence. These links overlap, rollers on pins, to make the complete chain. Most chain is made in inch-based sizes, because the standard chain dimensions were established before much of the industrialized world had adopted the metric system. The basic chain size is given in terms of pitch, which is the on-centers distance between the rollers. The roller diameter is standardized at 5/8 of the chain's pitch dimension, so the common 5/8-pitch chain has a roller diameter of .391 inches. Unfortunately, no such uniformity exists in chain width, which varies a lot, as does sprocket thickness. Running a chain on sprockets which are too wide is usually a feat beyond even the most mechanically disinclined; unfortunately, it is also possible to run a chain on sprockets which are too narrow. The results of this are not good - the chain usually runs to one side of the sprocket, concentrating a majority of the load on one side of the chain, lowering its strength considerably and greatly increasing both load and wear. The loads on a chain are astounding. An average large-bore motorcycle in first gear can easily develop 1500 pounds of pull on the drive chain. The load-bearing area on the drive pins is about .075 square inches in circular contact, in reality, much less. The best-case loading for each pin is on the rough order of 20,000 pounds per square inch! With this kind of load, chain wear becomes less of a mystery. The loads imposed by the engine are only part of the stresses inflicted on the chain. If you watch a motorcycle in motion, you will see that the slack side of the chain does not simply droop. Instead, it snakes and curves in a wavelike motion induced by its tendency to try to wrap itself around the sprocket. Stresses involved can be quite large. This threshing about adds to the relative motion between the pins and links and wears the chain out faster. Motorcyclists often refer to "chain stretch." This term is somewhat misleading. Chains do not actually stretch materially; any load large enough to appreciably stretch a chain would be as likely to snap it right in half. The stretch referred to is the growth in overall length of the chain due to wear in its many moving parts. The chain's pins pull very hard against the bushing walls and most of the wear occurs at those contact points. Loads carried by the bushing/roller contact surfaces are just as large but spread out over so much area that the pressure at any given point is much less than at the pins. In the normal course of events a chain's pins will be worn to their service limits long before the rollers are in any trouble. A chain is ready for replacement when stretch exceeds 2 to 2.5 percent. On a 5/8-pitch chain, this figures out as about .0125-.0156" of slack per pin joint. Measuring each joint with a micrometer is not necessary. For example, a chain measuring 65 inches has reached its service limit when its length has grown to 66.3 to 66.63 inches. As the chain wears, the effective pitch between the links becomes greater. The chain's pitch becomes slightly longer that of its sprockets, causing the rollers to ride up on the teeth and apply pressure where the sprocket is narrow and weak. A properly-designed sprocket is designed to engage the chain's rollers gently, ease them down to the base of each tooth - where the load is taken - and then disengage smoothly and send the chain away. As the chain rides up on the teeth, sprocket wear increases dramatically. It would be nice if the sprocket makers would tell us how much a chain may stretch before it would no longer fit within the design limits of its the sprockets. Unfortunately, most sprockets come bulk packed, or, if we are lucky, they might be blister-packed to prevent them from being beaten up in shipment. Chain wear can be kept to a minimum by keeping it clean and properly lubricated. Gasoline, kerosene/paraffin, and cleaning solvent are definite no-nos for cleaning chain. They can eat the O- ring seals and then hang around to contaminate the lubricant. Wipe any dirt of sand off with a cloth, then apply your favorite lube. Specially-formulated chain lubes usually spray on like a thin oil to better penetrate the crevices and then congeal to better prevent being thrown off. Inexpensive non-O-ring sealed chains require much more frequent attention. On an unlubricated chain the friction between links can cause temperatures to rise to the point where the links can actually weld themselves together, putting a permanent kink in the chain. New chains have a breakin period, and that's when they have special need for proper lubrication. If their pins are well-oiled the loaded surfaces will be burnished smooth, leaving them in better condition to resist wear. Without adequate lubrication the surfaces will scuff and gall, greatly accelerating wear. The chain final drive has come to become the mark of the sporting machine. It is lightweight, mechanically efficient, inexpensive, and compact. Chain technology is still developing, and it's likely we'll see chain drive used for a long time. ===================== Q: My engine has a magnetic drain plug. Whenever I change the oil, it's always covered with tiny metal splinters and spooge. Does this indicate problems in the engine? A: Probably not. The magnet's purpose is to attract ferrous spooge. The gooey mess is tiny iron filings from your cams, cylinder walls, and other wearing surfaces. It's basically the same sort of gick your oil filter traps. Small splinters and pinhead-sized chunks are usually pieces of your transmission's engagement dogs. It's normal to have *some* splinters even on carefully-ridden machines. A lot of them indicates missed shifts or worn shifter components. Pinhead-size or larger flakes usually mean the case hardening is coming off the gears. That's a bad sign. (continued) Subject: rec.motorcycles FAQ of 93.10.01 (Part 4 of 6) ===================== Q: The front brakes on my bike make a buzzing noise. I've looked all over and can't see any loose parts. What is it? A: You probably have drilled or slotted rotors. The holes often make a noise as they move past the pads. Some bikes have floating rotors which can make intermittent noises. In either case it's nothing to worry about. Q: Are drilled or slotted rotors more efficient than solid rotors? A: There are many different reasons rotors are drilled or slotted. Sometimes the rotors are drilled to lighten them, though your weight savings is probably negligible. Honda claims the discontinuities help braking in the rain and provide an escape route for mud or rust. Fred Puhn's "Brake Handbook" says, "Some rotors have slots or holes machined into their contact surfaces. These reduce hot-gas and dust- particle buildup between pad and rotor. Although fade caused by gas buildup is less for a disc brake than for a drum brake, some fade still occurs. This is more prevalent with large brake pads, because the hot gas has a harder time escaping than with small pads. Therefore, slots or holes have greater effect in racing, where pads are large and temperatures are very high." Newcomb & Spurr's "Braking of Road Vehicles", 1967, tells us the mass of the rotor is the primary factor for preventing brake fade. When the rotor mass has absorbed enough heat, the brake will fade. Vented rotors and ducting schemes will cool the rotor faster, but it takes time; in rapid repeated braking cycles vented rotors do little better than solid ones. Carroll Smith's "Prepare To Win", 1975, says "Lately you may have seen discs with tangential slots milled in the friction surfaces or holes drilled in a tangential pattern normal to the friction surface. This is an effort to wipe the "fireband" or boundary layer off the disc before it reaches the point of contact with the pad and to provide the very hot particles of friction material worn off with some place to go other than the operating area." ===================== Q: I have a 1973 Kawasaki Z-1. My owner's manual says it should run premium leaded fuel. Will it hurt the engine to run unleaded? The local shop says they need to install hardened valve seats for $400. A: No. Your Kawasaki already *has* hardened valve seats. Engines with aluminum cylinder heads must have seat inserts, as aluminum is not a suitable seat material. Someone is trying to rip you off. *** Lights: Q: I've seen ads for light modulators that flash the headlight and brake light. Are these really useful? Should I buy one? A: In general, no. Many states and municipalities prohibit flashing lights (other than turn signals) except on authorized emergency vehicles. Check your local laws before you buy. Even if you're legal at home you still might pick up a ticket elsewhere. Flashing lights often infuriate cagers, who will then mess with you. Generally, the cagers win. The flashing is also *very* bad for halogen bulbs. Expect your headlight life to be significantly decreased. *** Personal Equipment: Q: I'm considering the purchase of a new helmet. The one I have doesn't feel too good for some reason, even though it's the right size. How can I tell when a helmet fits right? A: First off, helmet sizes are like shoe sizes - they're only a general guideline. Don't expect a size 8 to be the same size from two different manufacturers. Every brand of helmet is shaped differently inside. Of each brand, most models are also different. The only way to find a properly fitting helmet is to cruise the local shops and start trying them on. Try ALL of them on, not just the expensive or pretty ones. Proper fit is more important than gaudy stripes or fancy certification. A properly fitting DOT-rated helmet is safer than a badly fitting Snell-rated helmet. The helmet should fit snugly. It shouldn't clamp your ears like a vise, perch on top of your head like a ferret wearing a coffee cup, or try to cave in your forehead. It shouldn't have any loose areas either. As long as the chin bar doesn't try to move your jaw back to your ears you're OK; in some helmets you're not *supposed* to be able to touch the chin bar. Many newer-design helmets have extensive padding in the cheek area. This padding can cause interference with glasses. You can sometimes get the cloth liner loose and cut reliefs with a razor blade. You can also pull the liner loose and add extra foam to adjust the fit in any loose areas. It's not a good idea to try to cut the styrofoam section away to adjust the fit - find a different helmet. Some people get upset at the idea of altering the fit of their helmet. The decision is up to you. ===================== Q: The wind and engine noise from my bike get to me after a while. Is it safe to wear earplugs when I'm riding? A: I've never had a problem. I keep a couple sets of cheap foam plugs in my bike's storage compartment; when I expect a ride to last more than half an hour or so I put them in. They lessen the noise a lot without blocking out sirens or screeching brakes. In some places it is legal to drive if you're deaf, but not if you are wearing earplugs. Check your local laws. ===================== Q: What's a good buy for a leather jacket? A: [email protected] writes: Things to look for in a leather jacket: OVERALL SUMMARY: - Thick leather is a must. This is what makes the difference between a motorcycle jacket and a fashion jacket. Protection: - Thick leather: heavy motorcycle leather (not "fashion" weight) 3-3.5oz weight or ~1-1.3mm thickness - Elbow pads - Shoulder pads Cut & Fit: up your back or the sleeves sliding up and leaving a gap at the wrist. - Sleeves really long - Back should feel a little "hunch-backed" when standing upright (more important on sport bikes than cruisers) - Try it sitting on the bike. - Fits closely in the forearms (sleeves zippered) - Down only to hips if you dislike bunching up that longer touring gear does. - Make sure to leave room inside the jacked for sweaters & such. - Don't buy anything you haven't tried on [conflicts w/ later suggestions for buying mail order] Comfort/Convenience: - Zipper front - Flap behind zipper to keep out the cold - High collar - Snap-down collar to keep it from slapping your cheek/neck - Vents (zippered) to let in air during summer; grommets at armpits - Removable (zip out) lining - Zippers at wrists to keep sleeves from sliding up (while you're sliding down the road) - Lower back support panel for when you fall down. - Stiff leather won't flap in the wind. - (Tie a leather thong through hole in zipper tab for easy zipping w/gloves) Durability: - Full-grain hides are preferred for repeated abrasion resistance, but split or top grain will probably work the first time you fall down. - Double-stitching Where to buy cheap: - Sears surplus outlet - J.C. Whitney catalog - Mail-order places (see ads in riding magazines) - Pawn shops - Check police stations for Highway Patrol officers wanting to sell used gear. (If calling used/pawn/surplus stores: Try to get as much info as possible over the phone. Give your size, etc. Be sure to say motorcycle jacket, otherwise they will say "Sure, come on over we've a fur lined brown leather coat and a pair of disco leather patch pants.") Miscellaneous: - [The MSF course I took emphasized comfort first, protection second -- being uncomfortable increases the likelihood of an accident, and it's most important to decrease that likelihood. Next important is protection, so that if an accident does happen, the damage is minimized. Discomfort includes too hot, too cold, too wet, too dry.] - Get a jacket you really like (off the bike too); if you're like a lot of folks, you'll wear it all the time anyway. - Don't worry about stiffness; some new jackets need to break in. - Hein Gericke jackets have it all, if you're willing to pay the price. Sometimes discounters may have them cheaper than most dealerships. (continued) Subject: rec.motorcycles FAQ of 93.10.01 (Part 5 of 6) ===================== Q: Is there anything that will clean a face-shield and also remove abrasions so that one can see through it better? A: [email protected] (Blaine Gardner) replies: What you want are Meguiar's Mirror Glaze Plastic Polish and Plastic Cleaner. They are very mild abrasives meant to remove scratches from plastic. For fine scratches just use the Polish, for bigger ones start with the Cleaner and finish with the Polish. The stuff is $5-8 bucks per bottle at most auto or motorcycle parts stores. Don't choke over the price too much, since both bottles will probably last you 10 years. The stuff works great on plastic watch "crystals" and compact discs too. ===================== Q: What kind of abrasion resistance can I expect from various protective gear? A: [email protected] (Blaine Gardner) replies: In the Sept. 1988 issue of Cycle they "road tested" several grades of leather, nylon and Kevlar. The two tests were dragging the material at 50 mph until it failed, and running a sample on an abrasion tester until failure. At 50 mph the results were: "Natural Armor" 3 oz leather 86' 0" "Strong Synthetics" Kevlar 22' 1" Codura Nylon 18' 3" "The Rest" 1.75 oz leather 4' 4" 2.25 oz suede 4' 3" Denim, 2 year old 4' 0.5" Denim, new 3' 10" Ballistic Nylon 3' 10" The results were a bit different on an abrasion tester, but the overall ranking was 3 oz leather, then the synthetics, and far behind those were denim and thin leather. Note that the best synthetics are 1/4 as effective as HEAVY leather, while light weight leather is considerably worse than the synthetics, and far worse that heavy leather. Of course multiple layers of any material is better than a single layer. Another point not covered by the table is that a material with a hard, slick finish is important because it resists snagging and tearing. The reason that Cordura nylon did so much better than the thicker Ballistic nylon is that the coarse weave of the Ballistic caught on a flaw in the road, and tore. The suede finish leather suffered a similar fate on the road. On the other hand, Ballistic nylon did much better on the abrasion tester where snagging was not an issue. [note from the Keeper: even the most abrasion-resistant clothing won't help if you're rapidly decelerated by a cage or a tree. A set of leathers won't make you proof against getting squashed, so be careful out there] ===================== *** Tires: Q: I'm having new tires put on my bike. Is there anything I should watch for? A: YES! Make sure the yoyos mounting the tire don't lay the wheel flat on the floor or let it fall over. This is a good way to bend a $200 brake rotor. Good dealers also use plastic rim protectors under the tire irons. This keeps from scarring your expensive polished or painted wheels. Some motorcycle tires are directional; that is, they are only supposed to rotate in one direction. Such tires are marked with an arrow. If your tire has an arrow, make sure it points the right way when you put the wheel back on. ===================== *** Law: Q: I'll be vacationing in [some foreign country] and would like to rent a motorcycle there. Is my [home country] license OK? A: In normal circumstances, as long as you are legal in your home country/province/state, you'll be legal elsewhere. There's also an International Driver's License - check your local licensing or motor vehicle authority for details. ===================== *** Other: Q: I am interested in/just bought a 19xx Yamahondasakiuki CNGSZxxxx and I was wondering how good it is and what I should watch out for? A: [email protected] (Loki Jorgenson) replies: You can do one of two things - 1) Check the anonymous FTP site ftp.physics.mcgill.ca (132.206.9.13) under ~ftp/pub/DoD for reviews for various bikes, as contributed by rec.moto members. If you don't have ftp access, you can send a request for a specific bike or the list of available reviews to [email protected] 2) If your bike hasn't already been reviewed, ask rec.motocycles, collect the responses, summarize them and forward them to [email protected]. Also, please feel free to submit your own review of any bike that you have already ridden. There is a TEMPLATE file available at the ftp site to serve as a guide for the information structure. ===================== Q: I'd like to get a bike cover. Where can I get one? A: Look in the magazine ads. Here are some points to consider before buying a cover: Plusses: keeps the sun, bird crap, and dust off your bike keeps feebos from sitting on it and covering it with drool and fingerprints may protect the bike from gratuitous vandalism Minuses: cover acts as a giant sail; makes it easier for the wind to tip the bike over dew and rain seep-through will collect under the cover, causing the bike to rust faster covers seem to be popular with thieves, who will sometimes destroy them trying to get them off you have to have some place to put the cover when you take it off. I use a $8 K-Mart plastic tarp. Two ends are tied to concrete blocks, the other two ends to chunks of 2x4. When I leave I simply flip the tarp off; when I get back I flip it back. It keeps the sun off while allowing plenty of air circulation. (continued) Subject: rec.motorcycles FAQ of 93.10.01 (Part 6 of 6) ===================== Q: I'm interested in adding a sidecar to my bike. What's the deal? A: [email protected] (Paul Spencer) says: I posted this once before, and have been mailing it out to those who ask. I'd love to work on it more, but my current schedule is a little insane. Have fun. I'll critique the sidecar FAQ you come up with if I have time. ....paul ===== sidecars ===== Having a sidecar is a lot of fun. You can ride all year, you can use it for errands a lot more, you can carry more people, you can go on much longer trips with others (since they can sleep in the sidecar). People come up and talk to you a lot more; they don't have the greasy biker' syndrome. However: sidecars are _NOT_ motorcycles. They handle very differently. I had over ten years and over 100,000 miles of riding experience before I got a sidecar; it wasn't very useful. Be prepared for a totally new experience. You can get yourself into trouble just as easily as you can on a bike; but you have many fewer options on getting yourself OUT of trouble. Unfortunately, many bikes these days are poorly made for attaching a sidecar. The entire outfit will be very difficult and dangerous to ride. Get expert advice in this field. (Even if you buy a bike and sidecar as a unit, it may be set up wrong; I'd say from informal looking around at sidecar rallies that about 50% of outfits are badly put together, and 20% are downright unsafe). The idea of having a sidecar that is removable is a poor one; a good sidecar unit is just that, a unit, which is never taken apart. Many desirable modifications that make the sidecar unit better - such as reduced trail, and flat-profile automotive tires - make the bike unrideable as a solo anyway. The only motorcycle manufacturer who sells sidecars is Harley Davidson. They are excellent sidecars, and Harleys are ideal for pulling them. Adding a sidecar to a Honda/Yamaha/Kawasaki/Suzuki /BMW motorcycle will void it's warranty; it will also make most shops refuse to work on your bike. Sources of more information: United Sidecar Association (USCA) 130 S. Michigan Avenue Villa Park, IL 60181 Regular magazine, books on building a unit, books on riding with a sidecar, books listing all available sidecars on the market. Also offer training courses on riding. National and regional rallies. Hack'd Magazine P.O. Box 17640 Portland, OR 97217 Monthly magazine. Better mag than the USCA. California Sidecar Garden Grove, CA (800) 824-1523 Wide range of sport and touring sidecars; handling packages. Motorvation Engineering 3702 Clifton Place Montrose, CA 91020 (818) 248-9631 Both sport and touring sidecars. BMW Motorrad of St. Louis / EML USA 4011 Forest Park Blvd. St. Louis, MO 63108 (314) 531-4010 Sell EML and Ural sidecars, along with a lot of parts for Steibs. Lots of handling improvement stuff. Great place, lots of free advice. Hitchhiker Sidecar Company 1665 Cumberland S.E. London, OH 43140 (614) 852-5373 Only make one touring-oriented sidecar, but it's well liked. ============================================= END OF FILE =============================================