Bottom Bracket Options
Sleeve option - #ISMFCM970P
New Press-fit Bottom bracket from shimano. Dura-Ace. SM-FC7800-P. Retail, about $30 a set.
Shimano's new press fit BB will allow for a bunch more options with bottom bracket widths and walls.
- SM-BB91-41A, MTB, Sealed, I-SMBB9141A
- SM-BB91-41B, RD, Sealed, I-SMBB9141B
- SM-BB91-42A, Unsealed, I-SMBB9142A
xtr - SM-FCM970 PRESS FIT w/ inner cover dura-ace - SM-FC7800 PRESS FIT
Allows for full carbon bottom bracket shells.
Wider shell spacing for improved suspension designs.
press releases say that scott has exclusive rights in the first year, but we all know how the bike industry really works. Yeti already has show bikes with it. The AS-R.
- Road, 86.5mm shell (symetrical)
- MTB, 92mm shell (offset 2.5mm on drive side)
- MTB, 89.5mm shell with a 2.5mm spacer on right side
If the shell is not sealed, an inner cover is needed:
- Road, FC-7800 Inner Cover
- MTB, FC-M960 Inner Cover
The inside of the shell needs a 41mm diameter 9.3mm deep ream on each side.
Reaming and Facing the Shell
I need to order a 1.625" reamer from KBC ($140.10)
Once that comes in, it will be reground to 41mm at:
Pacific Reamer & Cutter Service
Oakland, CA 94611