Deore mech jumping

mrfmilo
mrfmilo Posts: 2,250
edited July 2010 in MTB workshop & tech
Took the bike for it's first test ride and noticed a problem...when riding anything slightly rough or even dropping off a curb the mech jumps and hits the bottom of the chainstay?
It is a Deore Long Cage mech (hopefully to be replaced by a Saint short cage soon).

Is it set up wrong, or can I just pad the underside on the chainstay with foam?

Thanks
Marin

Comments

  • thel33ter
    thel33ter Posts: 2,684
    Is your chain too short, it sounds like the mech is being pulled too tightly and is at the wrong angle, near parallel to the chainstay, otherwise it might just be the chain, in which case a lizard skin should be fine till you get your Saint.
    And now you know, and knowing is half the battle
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  • nicklouse
    nicklouse Posts: 50,675
    yes it is a shimano mech.

    and yes. or a bit of rubber on the mech.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
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  • mrfmilo
    mrfmilo Posts: 2,250
    thel33ter Nope it's not too short, mech works perfectly apart from this.

    Nicklouse Just not had this before, had exactly the same mech on the old GT and it never did this - is there anything I can adjust to stop this?

    Cheers :)
    Marin
  • jay12
    jay12 Posts: 6,306
    the older long cage deores have seemed to be like this. my slx is no where near as bad as the deore i used to have. the short cage saint should be no where near as bad
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  • nicklouse
    nicklouse Posts: 50,675
    mrfmilo wrote:
    thel33ter Nope it's not too short, mech works perfectly apart from this.

    Nicklouse Just not had this before, had exactly the same mech on the old GT and it never did this - is there anything I can adjust to stop this?

    Cheers :)

    more info then.

    what is the frame?

    and yes it is a common shimano issue on some frames.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • mrfmilo
    mrfmilo Posts: 2,250
    Norco Torrent frame. Running 9spd on the back, single ring up front.
    Marin
  • The Rookie
    The Rookie Posts: 27,812
    Do you have a chain guide pulling the front of the 'slack side' of the chain up? That will increase the chance of it happening, can you relax that off a bit if you have?

    Simon
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.

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