Press-fit bottom brackets earned their reputation for creaking through a fundamental design problem: two separate cups pressed into a frame shell with no mechanical connection between them. The Wheels Manufacturing PF30 Outboard ABEC-3 Bottom Bracket solves this by threading the two machined aluminum cups together inside the frame, creating a unified assembly that stays put. Once the cups engage each other, they stop shifting independently, which eliminates the micro-movements that cause noise under pedaling loads.

The design fits PF30 frames with their 46mm inner diameter shells in both 68mm road and 73mm mountain widths. It also works in Specialized Carbon OSBB frames with the 61mm shell width when you add the optional cup spacers. The bearings sit outboard of the frame shell rather than inside it, which gives you a direct path to the bearings for service without pulling the cups from the frame. When the Enduro ABEC-3 bearings eventually wear, you press out the old ones and press in replacements while the cups stay installed.

This version accommodates 24mm spindle cranks from Shimano and other manufacturers using the Hollowtech II standard. The bearing inner diameter matches Shimano's 24.00mm spindle specification exactly. One note for FSA users: MegaExo spindles can measure anywhere from 24.00mm to 24.07mm depending on production tolerances, and the 24.07mm spindles will not fit these bearings. If you're running FSA cranks and encounter resistance during installation, Wheels Manufacturing offers replacement bearings sized for the 24.07mm spindle.... Read More