OK, so in my quest to get my old Trek 7000 ZX MTB running again after a long retirement, I am having an issue with replacing the bottom bracket.
The bike came with a Shimano LP25 that is marked BC 1.37 x 24. The spindle has LL 113 stamped into it.
So I ordered a Shimano UN55 BC 1.37 x 24 113mm.
They should be exactly the same size right? Well the new one seemed to be offset to the right (drive side) by about 1/8 inch, even though the spindles are the same length.
Now my front derailleur (STX-RC) won't shift to the largest outside sprocket even when the adjustment screw is all the way out. What can I do to correct this issue? I thought the only thing that mattered when replacing a bottom bracket was the thread size (68mm) and the spindle length.
Another strange issue is that the orginal LP25 has the threads on the L side, while the new UN55 has the threads on the R side. I could have sworn the threads were on the drive side when I removed the bottom bracket, but now I'm not so sure given the markings on it. Unless the bottom bracket was originally installed backwards? Would that explain the 1/8 inch offset discrepancy?
Thanks for any help. I'm really confused at this point.