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I have a 2011 Commencal Supreme DHV3 Team edition and I need to replace the bottom bracket. The problem is that I am confused about what the correct model to buy is.

The tech book for the bike states:

  • BOTTOM BRACKET WIDTH Type Cranks 83mm Press Fit Shimano BB92

However, doing some online googling I found this thread where the poster has been told that he should buy either

This page states that BB91 and BB92 are identical, however this doesn't seem to be the case to me as the BB92 has a shell width of 91.5mm

I'm puzzled as they have different BB numbers and different widths too (the BB92 has a shell width of 91.5mm). I would naturally just choose the BB92 from the Commencal tech book, but can't find any Shimano BB92s for sale in the UK.

Which model do I go for? Will a BB71 do?

Unfortunately I am not in a situation where I can look at my existing bottom bracket as it has transpired that an incorrect BB was fitted to my frame when I had it serviced about 6 months ago, and I am no longer in the same country...

share|improve this question
What did Commencal say when you contacted them? – PeteH Jul 26 '14 at 14:40
Also, I replaced a press-fit bb on my road bike last year. There are separate tools both for removing and for fitting, each tool cost a couple of times more than the bb itself. Unless you specifically want to do it yourself, it may be less hassle, and also cheaper, to take it to your LBS and letting them find out what is needed. – PeteH Jul 26 '14 at 14:48
I'm actually in the Alps at the moment. The LBS phone Commencal but, being a Saturday, no one was in. The mechanic wanted to check with them but thought it was 'BB92 83mm'. So again a different width. Maybe he was just referring to the crank width... – ninjaPixel Jul 26 '14 at 15:01

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