Bottom Bracket compatibility? I have an older Wabi Classic cycle which comes with TH Industries BB-7420AL 68/103 that seems to creak. I believe its called squared tapered. Its a single speed. Missing Cranks



I want to change the Bottom Bracket and Crankset to a new Shimano/ Sram with I think its called external threads? How do I buy both?

Can it be changed?
You can indeed replace the square taper cartridge with an external bearing bottom bracket and fit new cranks.

Shimano's system is HollowTech II, SRAMS's is GXP, there is also FSA's MegaExo. I believe that the bottom brackets and cranks of each of these systems are not cross compatible.

Note that many bottom brackets are labeled as either 'road' or 'MTB'. Road brackets are typically for 68mm wide BB shells while MTB brackets are typically for 73mm shells.