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  1. #1
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    Sheared water bottle bolt

    Not really sure if this is the right forum for this question. It is somewhat related to the frame...

    The bike I recently got came with cheap aluminum bottle cage bolts. While installing a plastic pump bracket, I sheared off one of the bolt heads (didn't torque it down tight, I'm guessing the bolt was cracked). Now there is about 2 mm of bolt sticking out of the threaded boss. I tried some pliers, but there's not enough to grab on to, and what it can grip deforms and starts to round it off.

    So how do I remove it? Difficulty: it's the bottom-most mount on the seat tube. There's no way to get a drill in there head-on since the down tube is in the way.

    Would this be a job for the LBS? Or am I hosed?

  2. #2
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    Use a small file to cut a groove across the stub remaining from the bolt, that is if you haven't already destroyed the exposed bit of stub. Put bit of oil on the treads and let it sit a bit. Use a screwdriver to spin the stub out.

    If you don't have enough stub to make a groove use a pointed punch and tap an indentation off-center into the top of the stub. Then use a drift or an awl, point inserted into the dent, and tap the end of it to drive/spin the stub counter-clockwise. Be patient and deliberate.

    Good luck.
    I don't rattle.

  3. #3
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    Well?
    I don't rattle.

  4. #4
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    Quote Originally Posted by Berkeley Mike View Post
    Use a small file to cut a groove across the stub remaining from the bolt, that is if you haven't already destroyed the exposed bit of stub. Put bit of oil on the treads and let it sit a bit. Use a screwdriver to spin the stub out.
    This. I've sheared many bolts, and always used this method effectively.

    Except for that one rotor bolt which had to be drilled. Now that was nerve wracking.

  5. #5
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    Quote Originally Posted by mattbryant2 View Post

    Now that was nerve wracking.
    This is one of the things that can make this so hard. The breakage is bad enough but often the timing or location put stress on the subsequent extraction. Add to that a lack of skill or familiarity with the repair process and before you know it you have ruined whatever stub you had. It is usually at this point that someone takes it to a wrench, a mechanic, a machine shop who have to work with a worse situation.

    Been there.
    I don't rattle.

  6. #6
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    Quote Originally Posted by Berkeley Mike View Post
    Well?
    It's been a busy week and I haven't had a chance to take the time I'd need to do this right. I plan on taking a crack at it tomorrow, though.

    I don't think there's enough there to file a groove. I might have ground a bit too much of it away in my impatience with the pliers, so I might go straight to the punch and awe method you suggested.

    I think I have some sewing machine oil somewhere on hand. Failing that, I'll probably use gun oil. That should penetrate the threads, I believe.

  7. #7
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    Quote Originally Posted by Berkeley Mike View Post
    Add to that a lack of skill or familiarity with the repair process and before you know it you have ruined whatever stub you had. It is usually at this point that someone takes it to a wrench, a mechanic, a machine shop who have to work with a worse situation.

    Been there.
    Yeah, this is one reason I'm hesitating a little.

  8. #8
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    Quote Originally Posted by Berkeley Mike View Post
    Use a small file to cut a groove across the stub remaining from the bolt, that is if you haven't already destroyed the exposed bit of stub. Put bit of oil on the treads and let it sit a bit. Use a screwdriver to spin the stub out.

    If you don't have enough stub to make a groove use a pointed punch and tap an indentation off-center into the top of the stub. Then use a drift or an awl, point inserted into the dent, and tap the end of it to drive/spin the stub counter-clockwise. Be patient and deliberate.

    Good luck.


    Finally found time today to sit down with a beverage, a file, a screw driver, and some gun oil. 15 minutes of fiddling later and I got it out.

    Thank you, Mike. This turned out to be a lot simpler than I thought it was going to be.

    Also turns out I had some bonus stainless steel bolts in the random crap box that work in the place of the original bolts (the heads on these Al bolts are pretty soft, I could feel them deforming while removing the set I hadn't even touched until today).

  9. #9
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    Very well done, my man!

    Happy New Year.
    I don't rattle.

  10. #10
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    I was a collision tech for 30 years to extract broken bolts I used left hand drill bits and a drill the goes in reverse the thought of left hand bits is when it is drilling the holes some times the bit will make the bolt back out for you if not once a hole is drilled you can install an easy out to remove the broken bolt

  11. #11
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    Quote Originally Posted by bankofdad View Post
    I was a collision tech for 30 years to extract broken bolts I used left hand drill bits and a drill the goes in reverse the thought of left hand bits is when it is drilling the holes some times the bit will make the bolt back out for you if not once a hole is drilled you can install an easy out to remove the broken bolt
    Left-hand bits, especially carbide ones, are the savior of any mechanic. You beat me to it.
    Unfortunately he didn't have room to use a drill so I'm glad one of the other suggestions worked out!
    -Matt
    Long time auto mechanic, newbie MTBR.
    http://www.SpoolinUp.com

  12. #12
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    Cramped spaces are often reachable with right-angled drills. Just as with left-handed bits, now we get into some pretty special tools, far more involved than a file, a punch, and a screwdriver.
    I don't rattle.

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