Animation of The Bushnell Eccentric Bottom Bracket

The original design had no center support, and narrower locking sections. In newer titanium bikes with relieved bottom bracket shells, the center wing section could deflect. The energy of tightening the bolt was partially absorbed by this deflection and couldn't be transferred to the locking circumference sections like it could be in consistent diameter shells.

No longer able to rely on contact throughout the entire bottom shell, the new Bushnell featherweight design has a center support to stop this deflection from happening. It also has slightly wider sections for the locking circumference. The combination of these two modifications has solved any issue that we were experiencing with newer 'relieved' bottom bracket shells.