Originally Posted by
I_like_cereal
They are friction. So then I would just need to "dial in" the shift? But, if the chain is narrower then wouldn't the front d shift funny. I assume the 10 speed chain is narrower and the 9 speed front d is wider to accommodate the wider 9 speed chain.
Not enough difference to matter.
My rain bike has 10 speed drivetrain, but I'm using a "6-speed" front derailleur AND crankset from 1985. Works perfectly.