Tiagra crank wobble

willow71uk
willow71uk Posts: 114
edited October 2013 in Workshop
My Tiagra crank has a slight wobble. When i hold both arms there is some play i am able to move it backwards and forwards a couple of mm. Should this not be solid or should there be some slight play? Is it just a case of re-tightening it with a Hollowtech installation tool?
Thanks.
Paul

Comments

  • Pauldunk
    Pauldunk Posts: 42
    Paul,

    It seems like the left crank arm is loose, as you mentioned tighten it back up. When you do this do not apply to much pressure on the arm as you turn the hollowtech tool. Nip it up, back it off and nip it up again. To help you watch the 'how to video' on the Hope website, I think its the install crank video.
    Just to add, my Tiagra crank on my road bike had a bloody creak when pushing hard, sorted this by putting alittle grease on the spline and refitted.

    Regards,

    Paul.
  • nicklouse
    nicklouse Posts: 50,675
    willow71uk wrote:
    My Tiagra crank has a slight wobble. When i hold both arms there is some play i am able to move it backwards and forwards a couple of mm. Should this not be solid or should there be some slight play? Is it just a case of re-tightening it with a Hollowtech installation tool?
    Thanks.
    Paul
    what direction is back and forwards?

    if bike direction then worn bearings or lose cups.

    if you mean in and out or across the bike then slacken the pinch bolts off add preload and then tighten the pinch bolts a bit at a time till the correct torque is reached.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • willow71uk
    willow71uk Posts: 114
    Cheers for the speedy reply. Yes its in and out across the bike. I will get a tool and tighten it.
  • keef66
    keef66 Posts: 13,123
    At the very least you'd need to undo the pinch bolts before tightening the plastic preload cap, but the best bet is to take the LH crank off and reinstall it.

    Unscrew and remove the 2 pinch bolts with their washers and fish out the safety tab from the gap in the crank. Unscrew and remove the plastic preload cap, then remove the crank.

    Clean up the splined mating surfaces and check for signs of damage. Apply a light smear of grease and reinstall the crank. Just whack it with the flat of your hand to ensure it's fully seated, then install and tighten the plastic preload cap. Just finger tight; overdo it and you'll reduce the life of your bearings.
    Then install the safety tab and the 2 pinch bolts with their washers. Tiny bit of grease or copperslip on the threads. Tighten them alternately and incrementally. Pretty tight, but don't go all gorilla on them or you'll strip the threads.

    If that doesn't stop the wobbling, maybe your BB is knackered.

Categories