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  1. #1
    Junior Member
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    malvern star (sportstar) bottom bracket solution

    Hi folks, I've recently taken on a sportstar frame, late 70's early 80's at a guess, which seems to have an annoyingly unique BB. no thread with locking tabs. the bb itself has a lockring on the non-drive side only and it's a cotter pin design.

    the bb I have is still useable so things aren't desperate as yet, but I'm spending alot of time on this bike and I'd like to fit a sealed square taper to give me a wider and lighter selection of cranks. anyone out there had the same problem? Is there a solution?

  2. #2
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    I just measured the shell, 38mm ID. if that helps any?

  3. #3
    Old fart JohnDThompson's Avatar
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    38mm ID? That's going to be tough. I suspect that it needs some sort of proprietary Malvern bottom bracket. Are you in Australia? Perhaps you can scare up an old one someplace.

    I'm not sure if a modern threadless cartridge BB would work with a 38mm ID, but perhaps a shop would let you try it.

    Otherwise, you may need to braze a threaded sleeve inside the current shell, or pull the entire shell and replace it with a more standard one. Neither of these options is likely to be cheap, so unless you can do the work yourself you may need to consider another frame.

  4. #4
    Senior Member
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    You sure it's 38 mm nad not 40? 40mm is the size most Thompson style bottom brackets are. If you can find one, of course.

  5. #5
    Junior Member
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    yeah definately 38. The frame just isn't worth that much trouble (hi-tensile, pressed head lug and dropouts) so I'll just put up wit the massively heavy BB and crankset I have. put some money into a future build.

    thanks for your help guys!

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