Bottom bracket bearings sit directly in your pedaling force path. Every rotation, every watt you generate passes through this interface, which makes bearing quality and shell fit more consequential than their hidden location might suggest. SRAM's DUB bottom bracket uses their proprietary 28.99mm spindle diameter standard, splitting the difference between traditional 24mm and 30mm options to optimize bearing loads while maintaining reasonable chainline flexibility.

The BSA threaded shell eliminates the creaking issues that plague press-fit installations in aluminum frames. Threaded cups allow for proper preload adjustment and straightforward removal when service time arrives. Steel bearing cups thread into 68mm, 73mm, or 83mm shells depending on your frame's specification, with the cups machined to tight tolerances that ensure the spindle runs true through the frame.

DUB bearings use a double-row angular contact design that handles both radial and axial loads simultaneously. This matters because pedaling generates forces in multiple directions, not just the obvious rotational load. The angular contact arrangement distributes stress across a larger bearing surface than standard radial bearings, which translates to longer service life under real-world riding conditions.... Read More