Originally Posted by
sirious94
Hello
I am thinking of upgrading the crank on an old bike to 105 so i need an octalink BB. I took out the square taper BB in my bike (this was replaced 2 years ago, now it is a BB-UN54) On the BB i saw the usual markings (BB-UN54, 68, BC 1.37x24) then where on other BBs there is a number like 113 or 118, I read D-EL. What does this mean? What BBs are compatible with my bike? Is there a way to use a different number or are they completely not compatible?
Thanks
Your current bb length is irrelevant for a new 105 octalink crankset. The correct BB length for that crankset is a 109.5 such as the BB5500/BB7710/BB7700. Your frame is a 68mm, english threaded according to your current square taper crankset. You will have no problems finding a crankset and BB that will fit.