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Bearing size

flycop2000flycop2000 Posts: 55
edited April 2017 in Workshop
I am needing to replace the bottom bearing on my headset, its 40 x 52 x 8, 45 deg x 45 deg. I have a bearing that is 45 x 52 x 7, 45deg x 45deg. Is the 1mm difference in thickness crucial ?

Would I need to just fit it and see if there is any binding between the fork and the headset?

Posts

  • imposter2.0imposter2.0 Posts: 11,385
    Check those numbers - there's more than 1mm difference in the figures you are quoting. But yes, if the bearing is 1mm higher, it's unlikely to seat properly.
  • lesfirthlesfirth Posts: 1,204
    Flycop2000 wrote:
    I am needing to replace the bottom bearing on my headset, its 40 x 52 x 8, 45 deg x 45 deg. I have a bearing that is 45 x 52 x 7, 45deg x 45deg. Is the 1mm difference in thickness crucial ?

    Would I need to just fit it and see if there is any binding between the fork and the headset?

    What else could you try?
  • The existing bearing is 8mm thick but I had a spare 7mm one in my tool box, just wondering if I could use it to save ordering one from Wynch?
  • keef66keef66 Posts: 13,123
    Well if one has an inner dia of 45mm and the other is 40mm possibly not. Or is that a typo and they have the same internal dia?

    If they are the same bar the 1mm difference in thickness, it would only take a couple of minutes to try it and see. If it locks solid when you tighten the topcap you'll know that 1mm was crucial...
  • Sorry about delay in replying. Its a typo error, both bearings have the same external and internal dimensions.

    I'll try the 7mm bearing and see what happens.
  • The 7mm thick bearing works fine, no binding at all.
  • keef66keef66 Posts: 13,123
    Then I think you'll be good to go!
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