Bicycle Mechanics - What size ISIS BB do I need?

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View Full Version : What size ISIS BB do I need?


Dilettante
10-10-06, 09:43 PM
Hi Mechanistas, and apologies for what feels like a fairly basic question.

Would appreciate guidance on how to identify the BB size required for my frame.

I have a never-built Look KG111 frame, for which I'm gathering bits. I would like to use a set of compact FSA Gossamer ISIS cranks and Centaur for the rest of the drive train, and wondered what size ISIS bottom bracket I'll need. I know I it needs to be English threaded, but they come in various sizes - 108 mm, 113 mm, etc.

Any advice welcome!

Regards from sunny, dry and windy Melbourne,

Greg


TallRider
10-11-06, 12:11 AM
ISIS was supposed to standardize bottom-bracket lengths, so if you're using a double crankset (I assume you mean a compact double) for proper chainline with a road (130mm-spaced) rear hub, you'll want 108mm. 113mm is for road triple (or mtb double if anyone wants to do it) and 118mm is for mtb triple.

Dilettante
10-11-06, 05:35 PM
Thanks timcupery,

Confirmed my initial thoughts. Much appreciated.

Greg