Mountain Biking - Bottom Bracket Size

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chadasm
08-18-06, 01:13 PM
I've searched and I can't find an answer to this. my current frame has a 68mm bottom bracket shell and I'm going to a frame with a 73mm shell. I believe I need a new bottom bracket that is 73mm, but to keep everything else the same, do I need to get a different size spindle as well? Like if I have a 68, 113, do I get a 73, 113 or does it need to be larger because of the larger shell?

dminor
08-18-06, 02:04 PM
You won't need a new BB if it is a 'universal' one - - it should say 68/73 if it is. A lot of Race Face BBs are both; a lot of FSAs are one-width-only. Pull your BB and look at its markings; or if you know the exact model, look it up on the company web site.

Should not need a longer spindle; 68/73s are made for the wider width. The non-drive-side cup just screws in farther to fit a 68 along with a drive-side spacer.
a2psyklnut
08-18-06, 03:29 PM
Stick with a 73x113. the 68 or 73 denotes the bottom bracket shell width. The 113 denotes the spidle width.

chadasm
08-18-06, 03:36 PM
Thank you both. I wasn't sure if I needed a wider spindle for the wider shell or not.