Ask the Editors: Chain and Sprocket Combo Platter?
Dear ATVC:
Picked up a new chain for my Raptor 660. The sprockets look fine, still have good teeth left but the dealer said I should replace both sprockets whenever I replace the chain. Truth or moneymaker?
Truth but not always. The reason for this advice is simple: A worn out chain is doing damage to your sprockets. You may not be able to visually inspect the type of damage taking place but were you a human micrometer; you would realize that brand new components have significantly different dimensions than worn-out ones. This is crucial because mating fresh bits to out of spec ones is the surefire way to accelerate wear of the new parts. In short: slap a new chain on your worn sprockets and expect far less life out of the chain than when compared to replacing all three at the same time.
We did say “not always” and that’s because, though unlikely, you may have replaced your sprockets fairly recently before that worn chain had a chance to do too much damage. In that case, there may still be some life left in your cogs. Trouble is, it’ nearly impossible to tell how much damage has been done. Chains aren’t cheap so it’s a risk you would have to be comfortable taking. Hence in the long run, the only way to insure even wear to both the chain and the sprockets is to replace all of them at the same time and then we’re back to your initial question again. Dealer knows best in this instance.
