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Rounded Stem Bolt- HELP!!!

boris113boris113 Posts: 47
edited June 2007 in MTB workshop & tech
My headset has come loose and I need to tighten it up but one of the 3 allen bolts that clamps my stem around the fork steerer is rounded off. I don't want to destroy the stem or the fork steerer and so far, have tried a number of things including, penetrating oil, heat, brute force (accompanied with expletives) allen keys and those star shaped things similar to allen keys but nothing has worked. Any ideas? Thanks, harry

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  • GingersaurusGingersaurus Posts: 466
    If you can try and cut a slot in the bolt and use a screwdriver to turn it out.

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  • boris113boris113 Posts: 47
    Good idea but just had a look and one side of the head is sunk into the stem so couldn't get a hacksaw in.
  • nicklousenicklouse Posts: 50,675 Lives Here
    pics. or what stem and which bolt?

    nick
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  • rubber side uprubber side up Posts: 2,150
    You can get what i can only describe as a reverse threaded, tapered screw. Basicly, you drill into the bolt, and then screw this thing in, and in theory its supposed to unscrew it.

    <hr noshade size="1"><center><blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by EvilAlex</i>

    Something round here tastes bad. Could be plain old bad taste.
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  • boris113boris113 Posts: 47
    It's a Kona DH Primo stem. (2004???) Similar to the one in the link but with graphics on and there is a 3rd bolt between the other 2 that goes in the opposite direction. It is the middle one that is stuck. http://www.sunsetmtb.co.uk/shop/index.p ... gory_id=38
  • nicklousenicklouse Posts: 50,675 Lives Here
    so the other two bolts are they done up?

    nick
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  • boris113boris113 Posts: 47
    They are done up but the heads on those are fine so i can undo them without any probs.
  • boris113boris113 Posts: 47
    Might try and get one of those reverse taper jobs, that is what a mate suggested.
  • nicklousenicklouse Posts: 50,675 Lives Here
    and were you working on the rounded one with them done up? can you see the bottom of the bolt?

    nick
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  • boris113boris113 Posts: 47
    I left the other 2 done up so that it might take some of the pressure off the middle one but it didn't work. Yer i can see the bottom of it but it doesn't stick out.
  • nicklousenicklouse Posts: 50,675 Lives Here
    dont bother with an easy out could cause you more probs than you need.

    remove one bolt and find out the sizes of the head and the threaded part. now go and buy some top quality dril bits. one to drill the bolt head of the shaft. and the other to drill a hole in the remaining stud.

    now put the bolt back in and then drill the top of the rounded bolt. now you should be able to remove the stem.

    remove bars and place stem so that you can drill into the bottom of the remains of the bolt. you will get part way in when it should unscrew itsself. if not you should soon be able to put a screw driver into the hole (screw driver a bit bigger) and then unscrew it.

    then buy new bolts. if one went the rest could go as well.

    nick
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  • boris113boris113 Posts: 47
    Sounds like a good idea but either I will have no thread left in my stem or will be left with a tiny bit of metal still screwed into the threads?
  • nicklousenicklouse Posts: 50,675 Lives Here
    no, read it 2 drill bits different sizes.

    nick
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    older than an old thing that is very old</font id="size1"></center>
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  • boris113boris113 Posts: 47
    I understand that but in the bit with the thread (not the bolt head) it will either leave a tiny bit in the threads or take out the threads as well???
  • diver-boydiver-boy Posts: 47
    hammer a flat head screwdriver slightly larger than the space for the allen key into the bolt head and use the screwdriver!
    or weld a bolt onto the bolt in the stem and use that bolt instead!
  • rubber side uprubber side up Posts: 2,150
    Just a thought, try screwing a bolt into the other side of the stem, it _may_ spin the other bolt enough for you to be able to unscrew it by hand.

    <hr noshade size="1"><center><blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by EvilAlex</i>

    Something round here tastes bad. Could be plain old bad taste.
    <hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote"></center>www.mtb-bitz.co.uk - Bitz for you & your mountain bike. pinkbike
    </center>www.mtb-bitz.co.uk - Bitz for you & your mountain bike. pinkbike
  • AnonymousAnonymous Posts: 79,667
    Nicks Method is best.
    Or see if you can get any mole grips or something or other on the head.
    If not use the appropiate Allen Key size (5 or 6mm I guess) and get some araldite.
    Glue the Allen Key in a leave for however long the instuctions say. Then just undo the bolt, the allen key will be useless after though.

    ForBloodAnd Empire
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  • boris113boris113 Posts: 47
    The head is so badly rounded that I think if I did try the glue thing then the glue bond would just give up. I'm going to get hold of some spare bolts before I try anything, If I wreck that bolt then the bike won't be safe to ride with only 2 left and I don't want to be bikeless. The 2 drill bit sounds the best so will give that a go soon but am going to try stickign a bolt in the other way 1st because it won't trash any of the bolts. Thanks for all the help guys.
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