Ultra Torque: Cranks don't spin smoothly?

clazza
clazza Posts: 626
edited March 2009 in Workshop
Have put everything together following instuctions and using torque wrench but the cranks don't spin smoothly when I push by hand, stop after one revolution - is this normal? What could have gone wrong?

Comments

  • andrewjoseph
    andrewjoseph Posts: 2,165
    Lots could have gone wrong, we need more info:

    is this a new frame, has the BB been faced?

    Have you put the spacers in correctly?

    Is the weather sealing 'O' rings lubed?

    Is it aligned correctly?
    --
    Burls Ti Tourer for Tarmac, Saracen aluminium full suss for trails
  • clazza
    clazza Posts: 626
    It is a new Colnago Extreme C and not been faced - doesn't look like it needs it, as its a Ti BB insert and there's no paint / carbon on it

    Spacers are in - the wave washer, aligned (180 degrees) Didn't lube the O rings, no mention of that in the instructions - the ones on the cups?
  • john_wr
    john_wr Posts: 50
    Think you'll find it's just friction between the O ring seals in the bearing cups and the crank axles.

    New caranks usually have some grease on them, hence the moulded plastic sleeves which you discard. Might be worth re-assembling them with a bit more grease.

    My similar cranks only spin for one turn and are not like previous set-ups with a separate bottom bracket where the cranks would spin for a number of revolutions.

    John.
  • Monty Dog
    Monty Dog Posts: 20,614
    External bearing BBs don't spin like the old days of caged ball BBs where a quick shove and they'd spin for ages - it's drag from the bearing seals.
    Make mine an Italian, with Campagnolo on the side..
  • clazza
    clazza Posts: 626
    Thanks all, thought I'd mucked up installation and damaged the frame / cranks.

    Am I right in assuming that frame didn't need facing cos its a Titanium BB shell?