Originally Posted by nepaMTBer
On my second bike I need to replace the BB, but I have no idea what size type ect. i need. Ive tried getting it from the trek website but its not working. Its a 2004 trek 4900. Does anyone know?
You have the
Bontrager sport crankset. You need a 113 mm square taper BB. Measure your bottom bracket shell with a simple metric ruler to tell the length. I think i have the same frame on my 4300 and it is 73 mm.