How to Replace Your Motorcycle Chain and Sprockets

The connection between the engine and rear tire doesn't last forever; here's how to replace your bike's final-drive setup.

The motorcycle chain and sprockets are considered by the manufacturer to be consumables, meaning those parts are expected to wear out and be replaced at least once or twice during the expected usable life of the machine. Add to that one or any combination of neglect, hard usage, mis-adjustment, and/or harsh conditions, and you'll discover that a chain and sprockets replacement is in order for your bike. Note that we said both chain and sprockets; like many moving parts that wear in with each other during their lifetimes, you must replace both at the same time in order to avoid causing an even shorter life for your new parts.

Replacing the motorcycle chain and sprockets is a fairly easy task, but there are some pitfalls to watch out for along the way. Here’s a quick photo tutorial on the job that will help you avoid those problems and get you back on the tarmac quickly.

Here are the basic tools you’ll need to replace your chain and sprockets. The important ones are a full-size breaker bar (third from right), an extension pipe for the breaker bar (far right), a block of wood to stop the rear wheel, a chisel to bend out the countershaft sprocket lockwasher (just left of the mallet), and a chain breaker and rivet link tool (blue box). Just as important: the proper factory torque specs for all nuts and bolts (paper, top).Photography by Andrea Wilson
1. After removing the countershaft cover, take the chisel and hammer/mallet and bend the lockwasher tabs holding the countershaft nut in place. Some lockwashers have two tabs, so make sure that you bend all the tabs back. And make sure they're bent back flat; if not, they'll keep the socket from fully seating on the countershaft nut, which could result in a lot of cursing and thrown tools in the shop.Photography by Andrea Wilson
2. Place the block of wood into the wheel so that the wood butts up against the swingarm and prevents the wheel from turning. Make sure the transmission is in neutral and that nothing is pinched between the wood and swingarm. Carefully hold the socket/breaker bar on the countershaft nut, and use the extension pipe to gain leverage to break the nut loose. Don't remove the nut yet.Photography by Andrea Wilson
2a. A very good tool to have that will break loose the most stubborn countershaft nut is an electric impact wrench. There are many cordless electric impact wrenches on the market ranging from $125 to $300 that will get the job done. These are better than the pneumatic impact wrenches because they don't depend on air pressure for their torque, and there are no hoses to deal with.Photography by Andrea Wilson
3. To remove the old chain, use a chain-breaker tool to push out one of the link pins (you can use a die grinder or other method as well), keeping in mind that if your chain isn't stock and has a clip master link, you'll need to remove the circlip and master link. It's best to do this on the rear sprocket so that it's stabilized while you work on removing the link pin. Remove the old chain, the rear wheel, and both front and rear sprockets.Photography by Andrea Wilson
4. Place the rear wheel sprocket side up, making sure the brake disc doesn't contact the ground; if it does, place wood blocks or a tire underneath to keep the rear disc from getting damaged. Install the new sprocket, and lightly hand-tighten the sprocket mounting nuts. Then use a torque wrench to tighten the nuts to factory spec in a crisscross pattern. Don't make the mistake of just tightening them "any ol' way." Replace the countershaft sprocket with the new one, install the lockwasher, and lightly tighten the countershaft nut.Photography by Andrea Wilson
5. Reinstall the rear wheel on the bike, and (unless you're a racer with specific needs) make sure the axle adjusters are set closer to the front; this will give you the most room for slack adjustment as the chain wears. Run the new chain over the sprockets, pulling the chain tight to run up the backside of the rear sprocket. Don't try to measure it any other way. Where the chain meets on the sprocket is where you'll push out the link pin.Photography by Andrea Wilson
6. Once you have the new chain cut to length (remember to measure twice and cut once), install the rivet master link, making sure that the O-rings are in the proper position (just inside of the outer plates). We prefer rivet master links to the old circlip master links because high speeds can potentially cause the circlip to come off (and, yes, this is despite glue, safety wire, silicone, etc.).Photography by Andrea Wilson
7. A rivet master link installation tool will have a block that allows you to properly press on the link plate and then a tool head that is used to peen over the end of each master link pin (note that the ends of rivet master link pins are hollow). Carefully tighten the tool to peen over the master link pin ends. Too much torque and you will end up cracking the master link pin end, rendering it useless.Photography by Andrea Wilson
8. Temporarily tighten the rear axle nut and use the wood block or other method to prevent the rear wheel from turning. Use a large torque wrench and extension pipe (or a pneumatic torque wrench gun if you have one) to properly torque the countershaft nut to factory spec. Slightly loosen the rear axle nut, adjust the chain-tension adjusters to get the proper chain slack, and torque the axle nut to factory spec.Photography by Andrea Wilson

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