• Hi all, I'm restoring an old steel road bike, British hand made in 531c tubing etc, nice Campag Nuevo record parts throughout, a real gem, but I'm having problems replacing the bottom bracket.

    Basically while the threads are English the bottom bracket shell width seems unconventional at 64mm from edge to edge of the shell. I tried fitting a standard 68mm BB and unsurprisingly it's too wide, i.e. the cups won't screw into the shell fully.

    So any ideas, I've looked online but can't find any useful references to 64mm BB's... Thanks in advance!

  • How about using 2 2mm spacers?

  • Hi Dan, thanks, yeah, that was my first instinct, so as a test using the bottom bracket I have I screwed in the cups equally, leaving the 2mm gap on both sides. Next I fitted the cranks to check what the chain line would be like and the inner chainring is really close to the driveside chainstay, so I think I need a different bottom bracket with longer spindle anyway.

    It just seems so odd that a UK frame builder would use a 64mm bb shell, it doesn't look like it's been faced, so guessing it was built this way, weird.

  • this diagram might help you get a BB with correct axle length

  • Hey I'm having the same issue.

    I've bought an old R O Harrison frame. It had wooden bearings. Of course I'm an idiot and threw everything away. Now I have an empty shell 64mm with a 35.5mm internal diameter.

    Any suggestion?

  • I was given this while back and seems to not have a regular size bb it is slightly larger
    I will measure it when I am home in a few days and if its correct your welcome to have it free of charge! Bike is no use to me after bending the frame
    If your based in London your welcome to take the full bike

    1 Attachment

    • 20201026_114719.jpg
  • Yes I'm in London! Let me know when you have the size, if you are not too far could be an idea! Thanks a lot.

  • Post a reply
    • Bold
    • Italics
    • Link
    • Image
    • List
    • Quote
    • code
    • Preview

Baffling bottom bracket shell... 64mm width, English threaded.

Posted by Avatar for GreatSince78 @GreatSince78