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Thread: BB threads

  1. #1
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    BB threads

    I've installed and uninstalled BB several times and when tightening the cup on the drive side, geared, the rule has always been to turn counter clockwise. Has this changed? The reason I ask -- I just purchased a new Race Face BB and both cups are threaded to turn clockwise to tighten. I have an older frame, mid 90's, has there been a change I am unaware of???

    More info: this is an old style BB, square taper, bearings 'in' the frame.

    Thanks In Advance for clarifying.

  2. #2
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    Reputation: Hardtails Are Better's Avatar
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    English threaded BBs turn the cups opposite directions, like you're used to. Italian threaded BBs turn both cups clockwise. Sounds like you bought an Italian BB. Frame that use that standard are rare, and are pretty much exclusively road bikes. So I think you just bought the wrong part. Mountain bikes still use BSC threading.

  3. #3
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    Thanks for clarifying. It indeed sounds like I've got an Italian BB, even though I ordered English.

    ...The pitfalls of buying parts online.

    Again, thanks for the help.

  4. #4
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    Reputation: Reignman's Avatar
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    English will have 37 x 1.24 TPI and Italian will have 36 x 1.24 TPI marked somewhere on BB

  5. #5
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    It turns out the BB had 2 left cups. Glad i didn't damage my threads.

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