Twanging/Creak from Campag record cranks

Chris5150
Chris5150 Posts: 107
edited October 2007 in Workshop
Think Im going to have to change my bikeshop!. Bike went in for a service last week, first ride out and I am getting a twang/creak sound from the crank area. It remains fairly constant ie it does not get worse when putting the pressure on. Did a 60 mile ride on saturday and the noise got progressively louder over the ride.
Bike is just about new, this was its first service having covered about 300-400 miles...pretty disappointed with the service, it was fine before it went in....have they possibly over tightened something?

Comments

  • Monty Dog
    Monty Dog Posts: 20,614
    There's very little to over-tighted on the UD cranks - the centre retaining bolt has a spring washer, so in theory can't be over-tightened. The only other things therefore are the chainring bolts and the BB cups. Again, assuming that the frame was prepped properly in the first place and that a suitable anti-seize was applied to the cups - I doubt the shop will have removed those for the first service - apart from making sure the cups were torqued in properly. Might be worth whipping the arms off and applying a smear of grease inside the cups and to the spindle to see if that makes a difference. As is typical with those sorts of things, it is usually a process of elimination rather than an easy to define fix.
    Make mine an Italian, with Campagnolo on the side..
  • Chris5150
    Chris5150 Posts: 107
    Thanks for the reply, comforting to know that not a lot can be overtightened. I am going to remove all the chainring bolts tonight, spray them with copper grease and bang them back in and generally check over all that area, hopefully it will be something simple like that
  • Chris5150
    Chris5150 Posts: 107
    Well I checked over everything last night and to my surprise I found out the central 10mm Hex bolt in the Hollow tech crank was fairly loose, so I tightened that up and had a little test drive and it seems to have stopped the noise.

    Has anyone else had this problem?...I thnnk I will start a seperate thread so people can search on it.
  • Bugly
    Bugly Posts: 520
    seems to be a 'design' feature of many of the new cranksets - the ability to loosen (similar problems on Raceface MTB cranks). Never happened with the old and simple (and Heavier) square tapered cranks. I tend to do a crank bolts tighten as a pre ride check nowadays :( .
  • aracer
    aracer Posts: 1,649
    Of course the instructions actually specify using thread lock rather than anti-seize on the cups out of preference, in which case no need to torque them in. Meanwhile there is a very big warning that you need to torque the centre bolt up correctly with a torque wrench rather than just use a normal allen key - the torque setting is 42Nm, which would be pretty hard to reach without a proper long torque wrench.

    Whilst I am inclined not to believe everything Campag say in tech instructions (they do still recommend installing ST cranks dry), they are generally pretty good and comprehensive.

    http://www.campagnolo.com/pdf/7225306_U ... _05_07.pdf
  • stoobydale
    stoobydale Posts: 535
    Bugly wrote:
    Never happened with the old and simple (and Heavier) square tapered cranks. :( .

    Campag Centaur 06 carbon chainset & Centaur BB is lighter than the new Hollow axel type including the BB cups. Also there is some evidence that the older style is more aerodynamic. :wink:
  • Chris5150
    Chris5150 Posts: 107
    So whats the outcome of it being loose?...mine was very loose and other than the creaking/twang like sound I felt no other side effects...I presume it would have to come off altogether to actually casue some form of failure?
  • Bugly
    Bugly Posts: 520
    Chris5150 wrote:
    So whats the outcome of it being loose?...mine was very loose and other than the creaking/twang like sound I felt no other side effects...I presume it would have to come off altogether to actually casue some form of failure?

    OUtcome may be that the splines can get damaged wearing out the cranks prematurley.
  • magliaceleste
    magliaceleste Posts: 748
    People have a tendency to use anti-seize instead of the recommended bright purple Loctite thread locker. I guess the shop should read the instructions where it clearly states that for the cups etc. I must admit I did it first time. When I redid it properly, any creaking was sorted.

    Old style BB's might not come lose (actually not true) but of course the BB is probably seized in the shell :wink: so you've got the opposite problem.
  • Bugly
    Bugly Posts: 520
    yeah those drive side cups were a pain in the arse. :)

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