3 piece crank removal.

Discussion in 'HOW TO' started by heyslugger, May 12, 2012.

  1. heyslugger

    heyslugger

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    Never taken anything beyond a pone piece apart. I am having trouble trying to get this JC higgens chain ring off. the rest of the bike is gone but i'd like to keep the ring. I took off the nut from the pin/bolt (top pic) that runs through the crank arm but the pin (coder pin) stays put and I can really see my next move. I am a little embarrased to even ask but how do I get it off? What am I missing? Thanks

    dan


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  2. aka_locojoe

    aka_locojoe

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    I think I've only done this once but if I recall... The pin is just wedged in place. With the nut still on but backed off, tap with a hammer and something to soften the blow to not damage nut. I say to leave nut on so you don't risk damaging threads. I'm sure someone will pipe up and tell us the correct way.
  3. deorman

    deorman

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    There is actually a tool for that, but I always used the leave-the-nut-on-the-end-to-save-the-thread-and-whack-it method. I hate cotter cranks. :roll:
  4. gcrank1

    gcrank1

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    With the nut backed off only about half way, take a bench vise (easier to do with it not mounted on the bench) and a socket that fits over the head of the cotterpin. Tighten the jaws down onto the nut and the socket with the pin between and give the jaw on the nut side a good whack, tighten a bit more and repeat. At some point it will break free and the head will go up into the socket. I have not messed up any cotters/threads or nuts this way on three cranksets since using this method.
  5. wimpy

    wimpy

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    I agree with the other RatRodders. Before giving it a good whack, you could spray some WD 40 on it and let it soak for a night or so.
    If that doesn't help, try a wheel dresser. Could be a nasty little job, but I've read about a guy who managed it this way.
    In case of the hammer: always keep the nut screwed on. Good luck.
  6. gcrank1

    gcrank1

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    I should add, that IF you must go the hammer route, support the crank arm from underneath with a chunk of wood, and as said, have the nut screwed on far enough so there is a lot of thread support, and give it a very good, straight down WAP. Little hits only peen. There is a good chance it will break free without breaking anything else this way, but you may bend the threaded shank some if you dont get a straight hit.

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