Originally Posted by
brianmr1
I have a trek 1500 9 speed and I was thinking of changing the bottom bracket. Is there a difference between a 9 speed or 10 speed bottom bracket?
Assuming the crank/bb are Shimano, the 9-speed is probably an Octalink and the 10-speeds would be a HollowTech II external-bearing type. They are completely different.