Timing Belts & Chains
About Timing Belts & Chains
Cam chains and timing belts connect the crankshaft to the camshaft or camshafts so the valves open at the right time. Chains are steel and run inside the engine, while belts are toothed rubber. Riders replace a chain when it has stretched, when the engine is open for a top-end rebuild, or a belt when it reaches its service interval.
Cam chains are sold by pitch and the number of links, shown in the listings as codes with a link count, such as 124 links. Count the links on your old chain or buy the chain listed for your engine. Both roller chains and silent chains are listed, and the type must match the engine, since they are different designs. Check whether a chain is listed as endless or with a connecting link, because that can decide whether the engine needs to be split to fit it. Belts are listed by tooth count and width, such as 88 teeth and 21 mm, and should be kept clean and not bent sharply.
Brands in this category include Parts Unlimited, Prox, Wiseco, Hot Cams and Moose Offroad. Pick your machine in the Ride Finder at the top of the page. A new chain is usually fitted with Tensioners & Pulleys and Sprockets. The wider group is Timing Components & Kits.
FAQs on cam chains and timing belts
What is the difference between a roller chain and a silent chain?
A roller chain has rollers that engage the sprocket teeth, while a silent chain uses flat plates with inverted teeth and runs quietly. They are different designs, so use the type listed for your engine.
How do I find the number of links in my cam chain?
Count the links of the old chain when it is laid out straight, or use the model listing. The link count is part of the specification, and a chain with the wrong count cannot be timed properly.
How often should a timing belt be replaced?
Replace it at the interval in the owner's manual, which is set by distance, time or both. Replace it early if it is cracked, frayed, oily or has missing teeth. Check the manual for your model.
Should I replace the sprockets when I fit a new cam chain?
Check them. A worn sprocket, with hooked or thin teeth, shortens the life of a new chain. Many riders renew the chain, sprockets and tensioner together when the engine is open, so one worn part does not ruin the others.
