Originally Posted by
Camilo
My understanding is that chains are compatible "downward" but not "upward", so a 10 speed chain would work with 9, 8, etc. but not the other way?
I tried to run a 10sp chain on an 8 speed drive train - the chain gets stuck between the chain rings. The same 10 sp chain worked fine on my son's 9 sp drivetrain though. So there is enough slop factor for you to go one speed up or down but probably not more than that.