I have a Shimano 104/64 4-bolt Octalink crankset which came from Trek with a 73mm x 113mm Octalink ES25 bottom bracket. I replaced it with a 118mm bottom bracket and see the front derailleur doesn't quite line up on the chainrings. Is this just a simple cable adjustment or will this half centimeter cause problems? Are these Shimano cranksets very close in tolerance so any deviation from factory specs will cause shifting problems? I've begun doing my own rebuilds and am just learning how to dial in the derailleur adjustments - there's definitely a learning curve here.

Anybody have any advice it would be greatly appreciated.

Thanks!

Chris

The only help I have to offer is that you might also ask this question in the Bike Mechanics thread. Its a good solid question.

Your chainrings are pushed outwards by 2.5 mm so you just need to re-adjust your front derailleur to account for the shift.

BTW, it won't just be a cable adjustment, you'll have to tweak the H/L set screws too.

Okay, so it will still work, I just have to tweak things a bit. Thank you!

Looks like I need to invest in a bike stand - making these adjustments with the bike on the ground and then taking it for a test run just isn't cutting it.

Chris