jtkai007
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Chain Maintenance.........Drive Chains
Chains are the most maintenance intensive parts of the bike. Use only the best chain and sprockets you can afford. If you can't afford some of the better upper tier stuff, save your money until you can. Don't cheap-out here.
Type of chain
Use only the best O-ring chain and keep it clean and lubricated. A properly maintained chain will last 15k to 20k miles, or more, depending on how you ride.
Type of master link
I will only use a rivet type master link. I've never had a clip type master link come off but as long as rivet on type links are available that's the only type that I'll use. I use o-ring chains and wouldn't use anything else.
Sprockets
Worn chains accelerate the wear rate of the sprockets and visa-versa. ALWAYS replace BOTH sprockets when replacing the chain and use STEEL sprockets on both ends. Aluminum rear sprockets are for racing and serve no useful purpose on a street bike. They cost twice as much as steel and wear faster. If you disagree with this, tough, it's your ass out there, not mine.
Fourth, ALWAYS replace BOTH sprockets when replacing the chain, Worn chains accelerate the wear rate of the sprockets and visa-versa. Last, when you do replace a chain buy the best chain and STEEL sprockets you can afford.
Lubrication
Keep it lubricated. Some people thinkthat since the chain pin lubricant is sealed in the chain with the o-ring they can back off on the lubrication and cleaning. This is NOT the case. If the o-rings dry out they will stop sealing the grease that they are holding and your chain becomes just so much scrap metal. For most riders the proper chain lubricant to use is as much a question of religion as it is technology. I'll just tell you what I do and you're on your own.
With every bike I've had in the last twenty years the manufacturer has recommended using either 90W gear oil or 30W nondetergent engine oil to lubricate the chain and kerosene to clean it. These OEM chains were mostly o-ring but not all. The only problem with these lubricants is that they were hard to apply and would coat your rear wheel with spooge but as near as I can tell they do the job.
with whatever the manufacturer recommends.
cleaning
Third, keep it clean, dirt will kill a chain in no time.
tension adjustment
Keep the drive chain tension adjusted properly - check it often. A misadjusted chain wears MUCH faster and is more likely to fail.
kk
Chain Wear
Almost all new bikes come with o-ring chains. There is no reason to use anything but an o-ring chain on a street bike. The only proper place for an old fashoned non-o-ring chain is on a race bike. Conventional chains have slightly less friction than an o-ring chain - that's why raccers use them. As long as I'm talking about race bikes, another stupid thing I see people do, mostly squids, is putting smaller chains on their bikes. They do this because racers do it. Racers do it because smaller chains have lower mass so that means you have less rotational inertia with a smaller chain which produces better acceleration. This is fine for a race bike but is stupid for a street bike. Actually it's stupid for a race bike too unless you're a good enough rider to be a pro. Pro's are the only people with sufficiently refined skills to take advantage of the miniscule increase in acceleration you'll get with a smaller chain.
I'm going to digress a bit and discuss how a chain wears. Let's start with a new chain and sprockets whose dimensions are perfect. Imagine that the chain is mounted on both sprockets. The sprocket on the engine (called the countershaft sprocket) is pulling the chain off the top and feeding it onto the bottom of the rear sprocket as the rear wheel rotates. The pulling force of the engine is transmitted via the side plates of the chain through the chain's pins to the rollers which exert a force on the face of the sprocket tooth to rotate the rear wheel. Since the distance between centers of all the pins of the chain is exactly the same as the distance between centers of all the sprocket grooves, all the rollers are equally sharing the pulling force of the engine. On my CBR600 there 44 teeth on the rear sprocket and about half, or 22, will have a roller in the groove. Therefore, each roller and pin will have 1/22 or about 4.5% of the load.
As the rear sprocket rotates the next chain roller to be fed onto the bottom of the rear sprocket approaches the next groove in the sprocket and it drops straight into the groove. The roller will touch the bottom machined into the sprocket at exactly the same time it touches the wall. The chain roller does not rotate as it enters the groove because it is exactly above the center of the groove. As the engine pulls the chain around, additional rollers are added at the bottom and pulled off at the top. Since the distance between centers of all the pins of the chain is exactly the same as the distance between centers of all the sprocket grooves all the rollers will drop in and pull out without the roller spining. This also means that the engine force that pulls on the chain is uniformly distributed among all the rollers that are on the sprocket at any given time.
This perfect world will last about one revolution of the wheel. As the chain flexes from straight to curved around the sprockets and back to straight, the chain's pins rotate slightly inside the bushing which is inside the roller. Every movement of the pin relative to the bushing when the chain is under tension (i.e. the engine is pulling the chain) wears away some of the metal on the pin and bushing. How much metal is worn away depends on the amount of of lubrication on the chain pin, the magnitude of the tension on the chain and how close the distance between centers of the chain pins matches the sprocket. The greater the mismatch, the more of the pulling force is concentrated on the pin and roller just ready to be pulled off the rear sprocket as the wheel turns.
When a chain wears, 99% of the wear takes place in the pin that goes through the side plates and the the bushing that the pin rides on inside the roller. As the chain gets worn the pin's diameter is reduced and the inside diameter of the bushing gets larger.
If you don't want to put up with all this chain maintenance crap, buy a bike with a shaft drive or a belt drive. One word of caution on drive belts, they work fine and last a long time but they are susceptable to little pices of stone getting stuck in the rear drive pulley teeth. This doesn't happen to chains because the sprocket teeth are too big and the wrong shape to catch a stone but a belt's rear pulley teeth are just the right size to catch a small stone and if one does get stuck it can trash the belt in no time (like hours). If you ride a belt drive bike on gravel roads check the rear pulley for stuck stones as soon as possible after you are back on the pavement. Also, if you have one of the few japanese made belt drive bikes you will probably have a hell of a time finding a replacement belt if yours breaks on the road. Harleys should be no problem as that's all they make now plus they almost never break unless a stone gets stuck in the rear pulley.
An alternative is to buy a bike without a chain. The options are belt drive and shaft drive. Both are almost zero maintainence.
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