The timing chain, also known as a "cam" chain, is one of the most overlooked parts of a motorcycle and should be regularly checked and maintained. As its name implies, the timing chain controls the valve timing of the motorcycle's engine. If it stretches, the bike will not run correctly, or will make unnatural sounds, so it should be checked and replaced every few thousand miles.
Remove the tank and any other component that will get in your way.
Remove the valve cover from the engine and set it aside. You should now see exposed valves, the timing rod, the timing chain and upper timing cog.
Using a large socket, turn the engine flywheel so that it reads TDC (top dead centre). This is to ensure that when the new chain is installed, the engine will still fire correctly.
Remove the side cover on the timing side of the engine. You should be able to see the lower timing cog inside.
Remove the lower timing cog.
Remove the timing rod to allow the upper timing cog to come free. Pull the timing chain up through the cylinder head, or down out of the side of the engine.
Drop the new chain through the cylinder head. Wrap it around the upper timing cog, and loosen the timing chain tensioner.
Wrap the chain around the lower timing cog. Replace the valve timing rod and be sure all bolts are tight.
Tighten the timing chain tensioner until there is no apparent slack in the timing chain. Do not over-tighten the tensioner or your motorcycle will run poorly.
Replace the side cover and valve cover.
Replace any parts taken off of the bike to perform the chain swap, start the bike and listen to the silence of a new timing chain.
If you ride a motorcycle with a Vee engine, you may only need to remove the timing chain cover to perform this procedure.
Any engine maintenance should be done with the aid of a certified manual for your bike. Incorrectly installing a timing chain could have disastrous consequences. Be careful. Take your time.