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  1. #1
    Senior Member Huge Zits's Avatar
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    What is this upper head-tube race supposed to look like?

    I purchased a used threaded fork with a partial headset. I only have the adjustable race, both caged bearings and seals, and the crown race.



    The adjustable race is like a cup that holds the bearings and the seal. If I put it on a flat surface, the bearings do not come in contact.

    Is the upper head-tube race supposed to have a protruding crown?

  2. #2
    Senior Member Huge Zits's Avatar
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    Adjustable race.


  3. #3
    Shop Wench
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    Quote Originally Posted by Huge Zits View Post
    Is that threaded? If so, the mating part has a top half that looks like a crown race, and a bottom half that gets driven inside the head tube.

  4. #4
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    Quote Originally Posted by laura* View Post
    Is that threaded? If so, the mating part has a top half that looks like a crown race, and a bottom half that gets driven inside the head tube.
    +1, you have the fork with the headset parts that attach to it. The companion parts are pressed into the head tube of the frame. There's a sort of symmetry, in that the upper H/T cup (cone) looks line the crown race, and the lower H/T cup is simmilar to the upper cup threaded on the fork.

    You can't just buy the related headtube parts because they're not usually sold separately, and in any case headset parts, while standardized in terms of frame and fork fit, are not interchangeable across brands or models of headsets.

    You'll need to buy a new headset. You'll need to know if it's 1-1/8" (all the same) or 1" which is more difficult because there are multiple standards. Refer to the headset guide here for the specs on the various standards.

    Most likely you have both a fork and frame that are ISO (British) but it's only about 90% odds so you'll want to measure the diameter of the headtube ID and fork crown OD (remove the race to do so.)
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  5. #5
    Senior Member Huge Zits's Avatar
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    All of the parts are JIS.

  6. #6
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    So you need a new JIS headset. If you can't find one at a decent price, PM me and I'll see if I have any left.
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    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

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  7. #7
    Old fart JohnDThompson's Avatar
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    Quote Originally Posted by FBinNY View Post
    So you need a new JIS headset. If you can't find one at a decent price, PM me and I'll see if I have any left.
    Failing that, have your LBS re-mill the fork and frame to accept ISO parts.

  8. #8
    Senior Member Huge Zits's Avatar
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    Right on. Thank you, everyone!

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