Niner

Bio-centric EBB Bottom Bracket

No more creaks, no more rounded EBB shells, no more debate about which system is best. Niner's new Bio-Centric bottom bracket system eliminates ALL of the issues with any eccentric bottom bracket system in an amazingly simple way: It''s a two piece design.

One of the Bio-Centric''s cups goes into the frame on the driveside of a normal 68mm EBB shell. The other goes into the frame on the non-drive side. There is an offset bolt that goes in from the non-drive side cup and threads into the drive side cup. The combination of this offset bolt, and the close tolerance of the Bio-Centric cup''s internal fit means that the threads for the bottom bracket line up automatically. Rotate one cup around the EBB shell, and the other will rotate with it, keeping the threads for the bottom bracket aligned. Any minor mis-alignment of these threads will be corrected once the bottom bracket and cranks are installed.

Simple, light, and strong, the Bio-Centric is the perfect solution to chain tensioning needs. With one 6mm hex wrench, the EBB can be adjusted on the fly and in the field, and it''s still the lightest EBB system on the market.

Welcome to the new standard in EBB design, the Niner Bio-Centric EBB.

This EBB is only made to fit Niner frames.

Confused about bottom bracket standards and what it is you need? Here''s a comprehensive look at the subject: The Bottom Bracket (Un)Standard blog post.