Campy9 drivetrain clatter

Discussion in 'Cycling Equipment' started by Gene Tolli, Mar 21, 2004.

  1. Gene Tolli

    Gene Tolli Guest

    Hi All,

    I'm finishing up a new bike build, and my C9 drivetrain is
    making a ruckus. Specifically: Chorus Mk2 12x23 cassette,
    SRAM 9s chain, Chorus9 metal shifters.

    The noise is cassette based, and only occurs when
    *up*shifting to the 15, 14, 13 and (less so) to the 12. I
    can quiet the clatter by gently pulling the shift lever, so
    it appears the rear der slightly overshifts to the right.
    There is no noise at all downshifting, and no noise
    upshifting from the 23 to the 16 (all of which correspond to
    riveted cogs).

    I've replaced the chain and tried a different cassette;
    neither helped. Dropouts are aligned. Shift housings have
    been cut flush, opened with a scratch awl and filed flat,
    and there are no wacky bends in the routing.

    I believe the Chorus levers have about 6-7000 miles on them,
    and have never been damaged.

    My thinking:

    1) Time for an Ergo rebuild. Seems unlikely.
    2) Double check the hanger alignment. I've checked it and it
    seems fine.
    3) I have crossed the shift cables under the downtube for
    smoother routing. Again, seems unlikely.

    Any help appreciated. Thanks in advance.

    Regards, Gene Tolli
     
    Tags:


  2. Kenny Lee

    Kenny Lee Guest

    Gene Tolli wrote:
    > Hi All,
    >
    > I'm finishing up a new bike build, and my C9 drivetrain is
    > making a ruckus. Specifically: Chorus Mk2 12x23 cassette,
    > SRAM 9s chain, Chorus9 metal shifters.
    >
    > The noise is cassette based, and only occurs when
    > *up*shifting to the 15, 14, 13 and (less so) to the 12. I
    > can quiet the clatter by gently pulling the shift lever,
    > so it appears the rear der slightly overshifts to the
    > right. There is no noise at all downshifting, and no noise
    > upshifting from the 23 to the 16 (all of which correspond
    > to riveted cogs).
    >
    > I've replaced the chain and tried a different cassette;
    > neither helped. Dropouts are aligned. Shift housings have
    > been cut flush, opened with a scratch awl and filed flat,
    > and there are no wacky bends in the routing.
    >
    > I believe the Chorus levers have about 6-7000 miles on
    > them, and have never been damaged.
    >
    > My thinking:
    >
    > 1) Time for an Ergo rebuild. Seems unlikely.
    > 2) Double check the hanger alignment. I've checked it and
    > it seems fine.
    > 3) I have crossed the shift cables under the downtube for
    > smoother routing. Again, seems unlikely.
    >
    > Any help appreciated. Thanks in advance.
    >
    > Regards, Gene Tolli
    Sounds like you don't have enough tension when reattaching
    the cable to the RD. The cable should be pulled tight and
    then bolted down.

    Kenny Lee
     
  3. geetee-<< The noise is cassette based, and only occurs when
    *up*shifting to the 15, 14, 13 and (less so) to the 12. I
    can quiet the clatter by gently pulling the shift lever, so
    it appears the rear der slightly overshifts to the right.
    >><BR><BR>

    Either the inner wire is not moving back and forth smoothly
    insiode the housing or you may have a broken EC-RE-111,
    spring carrier with a post, that breaks. You describe a
    broken post on the EC-RE-111..Easy to fix, not expensive.
    You can check it by removeing the lever from the hbar,
    taking the little cover off the back and you will see the
    opst end, at the 1 oclock of the shift guts. If it is loose
    like a loose tooth, it is broken.

    If nobody locally 'qui si parla Campagnolo', send it to me
    for a 1 day turnaround.

    Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St.
    Boulder, CO, 80302
    (303)440-3535 http://www.vecchios.com "Ruote convenzionali
    costruite eccezionalmente bene"
     
  4. Pete Biggs

    Pete Biggs Guest

    Gene Tolli wrote:
    > The noise is cassette based, and only occurs when
    > *up*shifting to the 15, 14, 13 and (less so) to the 12. I
    > can quiet the clatter by gently pulling the shift lever,
    > so it appears the rear der slightly overshifts to the
    > right. There is no noise at all downshifting, and no noise
    > upshifting from the 23 to the 16 (all of which correspond
    > to riveted cogs).

    All Ergos, including brand new ones*, have some play which
    means slightly too much cable is released when the thumb
    button is pressed. This is taken up next time the downshift
    lever is used.

    To avoid this, users either increase cable tension or live
    with it (and some have never noticed the flaw or deny it's
    a problem).

    * I've noticed this with three new pairs: One Chorus and
    two Mirages.

    ~PB
     
  5. Pete Biggs

    Pete Biggs Guest

    > Gene Tolli wrote:
    >> The noise is cassette based, and only occurs when
    >> *up*shifting to the 15, 14, 13 and (less so) to the 12. I
    >> can quiet the clatter by gently pulling the shift lever,
    >> so it appears the rear der slightly overshifts to the
    >> right. There is no noise at all downshifting, and no
    >> noise upshifting from the 23 to the 16 (all of which
    >> correspond to riveted cogs).

    I think the chain is noisier in the smaller sprockets
    because adjacent sprocket is only on tooth different - it's
    higher up - top of teeth are nearer chain, to rub against.

    ~PB
     
  6. Pete Biggs

    Pete Biggs Guest

    > Gene Tolli wrote:
    >> The noise is cassette based, and only occurs when
    >> *up*shifting to the 15, 14, 13 and (less so) to the 12. I
    >> can quiet the clatter by gently pulling the shift lever,
    >> so it appears the rear der slightly overshifts to the
    >> right. There is no noise at all downshifting, and no
    >> noise upshifting from the 23 to the 16 (all of which
    >> correspond to riveted cogs).

    ps. riveted cogs are not relevant because I get the same
    problem with Veloce 9-speed cassettes which have no
    riveted cogs.

    ~PB
     
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