Can't get SRAM Force cranks off

brit66
brit66 Posts: 350
edited August 2010 in Workshop
Using an 8mm allen key and nearly passing out with the exertion, I still can't budge it.

After this I took it to a (very small) LBS but they couldn't get it off either. He reckoned it might have been put on without any carbon grease and over tightened as well - can believe both.

I reckon an 8mm allen key attached to a scaffold bar just might do the trick but I'm all out of these.

Anyone got any ideas before I make the long trek to a larger bike shop?

Comments

  • balthazar
    balthazar Posts: 1,565
    Have you not got anything lying around you can use as an extension? I just undid the disc attachment bolts on my car with an old seatpost on the end of the 10mm Allen key (those nuts are loctited, tightened to 120KN, and probably hadn't been undone in at least a decade...!). Surely you have something to get you leverage? Good luck!
  • IIRC, the crank bolt should have only been tightened to between 40-50NM which is certainly in the realms of being able to tighten by hand with an ordinary 8mm allen key. It shouldn't have any carbon grease on it, as there is no carbon to carbon contact anywhere. There should have been a small amount of grease on the threads to prevent seizing, and if they were fitted from new this would have been applied from factory.

    How long has it been since the cranks were fitted/last removed as it sounds like it has just seized. You could try inserting the allen key so that it is pointing in the opposite direction to the crank arm, and then with one hand on the brake so that the cranks dont move, stand on the crank arm and then the allen key using your weight to turn the allen key.

    Otherwise you will just need to find some sort of extension such as a seatpost as bathazar suggested.
  • softlad
    softlad Posts: 3,513
    as above - carbon grease doesn't come into it and the LH crank should self-extract anyway as you un-wind the allen bolt. The RH crank should then pull out from the other side....
  • brit66
    brit66 Posts: 350
    Thanks for the advice.

    The bike is three years old, so shouldn't be that difficult to remove I would have thought.

    I stripped all the components off of it so can't do the standing on the allen key manoeuvre (but would have had it been together). I do have an old seatpost so will try using that for more leverage.

    Agree about the carbon grease, although the cranks are carbon, these won't be moving until that 8mm bolt is free.