What BB do I need?

joe1983
joe1983 Posts: 440
edited March 2009 in Workshop
Hi,

I recently bought an old Roy Thame frame and need to find a BB to fit. Could someone please explain to me how / what to measure to find the one I need?

Thanks in advance,

Joe

Comments

  • pete.whelan
    pete.whelan Posts: 788
    It all depends on what chainset you want to use.

    The frame is probably a standard 68mm wide shell and English threads. So choose your chainset and then match the shell sidth and threads to match.
    Recipe: shave legs sparingly, rub in embrocation and drizzle with freshly squeezed baby oil.
  • GavH
    GavH Posts: 933
    Had a similar problem with a frame I bought a while back. I measured across the BB shell and took a gamble on the threads (most are English). BBs are about a tenner at best unless you want something fancy, even a Shimano 105 HTII BB can be had new on ebay for £15. If you're in any doubt, take it to your LBS and ask them to fit something - let them do teh checking, measuring etc.
  • joe1983
    joe1983 Posts: 440
    Thanks for the info guys, just about to get the tape measure out! Do I need to take into account axle length when buying BB / cranks? Its for a fixed singlespeed

    Cheers,

    Joe
  • pete.whelan
    pete.whelan Posts: 788
    You need to ensure the chainring is in line (+/- 2mm) with the fixed sprocket; so depends on the drop out width of the frame and the hubs you are using.
    Recipe: shave legs sparingly, rub in embrocation and drizzle with freshly squeezed baby oil.