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  1. #1
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    5.7C, Revelation World Cup and headset slop: FSA expansion plug

    Not really a Pivot issue, but figured this was a good place to post (instead of the shock/suspension forum) since a few have the same frame and fork.

    My first venture into carbon steerer tubes and expansion/compression plugs. The fork is a Revelation World Cup tapered and the frame is the 5.7 carbon. Headset is Cane Creek 40.

    Reading all the instructions and doing hours of trial and error with spacers and insertion depth of the plug still gets me a tiny bit of slop around the lower bearing. Obviously if I go too tight the bearing pressure is not smooth. I'm frustrated a bit. Full disclosure: I cut the crown race, split it, so it'd go on the carbon tube easier instead of annihilating it.

    Took everything apart. Everything is there. If I take the front wheel off and pull up on the fork crown it is 100% tight and turns freely like a properly adjusted headset should feel. If I leave the top cap off and press down on the bar everything is tight and smooth. Somewhere in the expansion plug and top cap I'm having issues because the bearing preload is too much just hand tightening.

    How deep should I be inserting the 5mm-head plug?

    I've done everything per the usual traditional star fangled nut headset in terms of proper torque and blah blah that I've done the past 20 years. But something about this compression plug and its depth and the 6mm top cap is not perfect and I can't get the usual smooth bar turning with no slop in the headset.

    I don't think it's the split crown race; the split is turned to the side instead of facing front or back.
    Last edited by westin; 05-30-2012 at 10:38 PM.

  2. #2
    dog
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    i have zero experience with carbon steerers etc. but wouldn't splitting the race thingy allow it to expand a little under torque pressure (e.g. the the leverage of steerer tube against the headset)? and since it is kind of a wedge shaped fit between that and the bearing wouldn't that kinda create some leverage (e.g. with the wedging between the bearing and the race would expand the race even though a small amount) to allow some noticeable movement?
    i need to develop my crashing skills...

  3. #3
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    Got it! Called FSA tech support who walked me through everything I'd been doing. Then tech support said "it has to be a bearing and not the expansion plug."

    Took everything apart and sure enough the lower bearing "seal" had a raised cover that would not allow me to properly preload.

    That only took 7 hours of my time.....

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