Eccentric Bottom Bracket Modification
I know a few people around the country that are sponsored by Gary Fisher to ride 29" Rig Singlespeeds for the 2007 season.
The biggest complaint that they all have is the weight of the stock EBB cam. I figured that I would make a tool to trim some fat off the EBBs for these racers. Every gram counts.
The Fisher EBB measures 56.75mm (2.234").
One Possible Solution
It may be possible to shim the bb shell with some 0.050" delrin sheet or aluminum tube and use a Bushnell expanding eccentric.
This will be researched a bit.
The PVD Mod
102 gram weight savings.
Other Peoples Work
- creepyfriendly - 90 gram (unconfirmed) reduction
- mckeand13 - 80 gram (unconfirmed) reduction
Generic EBB Weigh In
This EBB cam is from a Zion Single. It's pretty generic and will serve as a good test peice untill I get the actual units in hand.
Making the Arbor
Machining the EBB
135 grams. 54 grams shaved off!