Niner Bio-Centric EBB:
This new system weighs just 117 grams with stainless steel 6mm bolt making it the lightest system on the market by far.
One of the Bio-Centricís 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 cupís 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.
The final part of the puzzle, the one that solves
all of the current EBB problems, are the flanges on the outside of the
Bio-Centricís cups. These flanges go ALL the way around the EBB shell, and clamp
down against the side wall of the shell as the offset bolt is tightened. By
using the sides of the shell to secure the EBB, Niner eliminates ANY possibility
of rounding out the EBB shell, one of the plaguing problems of current EBB
systems. In addition, by having 360į of contact around the EBB shell, the
Bio-Centricís cups SEAL the EBB from dirt and grime, which are the number one
cause of creaking in other EBB systems. This seal also keeps moisture out of the
system which is the key to noiseless EBB operation.
The Bio-Centric EBB
has gone through over a year and a half of real world and simulated fatigue
testing before we finalized the design, including a brutal CEN chain torque
fatigue simulation test that put the Bio-Centric through itís paces. The new EBB
design went 100,000 cycles with no slipping or breakage.
and strong, we feel like 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 itís still the lightest EBB system on the market.
Welcome to the new standard in EBB design, the Niner Bio-Centric