Designed to be a proper BB for installing Shimano™ Hollowtech II steel spindle cranks in either BB30, PF30, or Specialized’s OSBB frames. Our new patent pending Rubber Collet design keeps the cartridge bearings outboard of the frame right on Shimano™ spec for greater rigidity and free of frame/c-clip tolerance issues that other systems deal with.

Simply press in the longer non-drive-cup, then the shorter drive cup threads into it. As the drive cup threads in, our new expanding elastomer collet system expands to a precise limit evenly dispersing pressure for a super tight fit. With both cups connected and our collet set exactly to spec, there is no chance the bearings can come out of alignment or wiggle/walk out of the frame. This design also uses a compressible o-ring on the non-drive side cup to compensate for frame shell width discrepancies.

• New updated design with Rubber expanding collet.
• This BB is for Shimano™ Hollowtech II steel spindle road cranks only.
• Designed precisely to Shimano bearing stance & chain line spec.
• Forged & machined heat-treated 7075 T6 Aluminum
• For 68MM BB30, PF30, and Specialized Road frames
• Not for BB30a, BBRight, BB386EVO, BB86, BB92 frames
• Steel version:Enduro 2437
• Ceramic Version: Enduro 2437 Angular contact, Grade5 balls, ABEC5
• 68mm version cannot be used for MTB Cranks