XT Rear Mech Locking Up

tptvmbircn
tptvmbircn Posts: 782
edited April 2010 in MTB workshop & tech
Hello all,

I'm a bit puzzled and thought i'd give you guys a shout.

A strange problem with two XT mechs have happened, when in middle ring and starting from gear one the shifting becomes very rattly then the totally mech locks out as if the chain is getting stuck pulling the mech cage and lower pulley upwards to the frame and completely stopping me from peddaling...

I've got brand new cables, sleeves, full serviced mech, jockey wheels, rear cassette everything and its left me puzzled. Any ideas?

Cheers
Terry

Comments

  • nicklouse
    nicklouse Posts: 50,675
    Mmm middle ring? front.

    gear one.... is that the big or small cog at the rear or...

    but sounds like some chain suck going on here.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • tptvmbircn
    tptvmbircn Posts: 782
    Hi Nick,

    Its the middle ring front, big sprocket on the rear, but scratch that seems to be all gears on the rear, in top ring it runs fine (Bad for me as big hills and head wind today) eek.

    runs fine in all ranges on the workstand its when i'm out on the tracks it does it. very puzzled :?
  • bomberesque
    bomberesque Posts: 1,701
    sounds like worn middle ring causing chainsuck?
    Everything in moderation ... except beer
    Beer in moderation ... is a waste of beer

    If riding an XC race bike is like touching the trail,
    then riding a rigid singlespeed is like licking it
    ... or being punched by it, depending on the day
  • bails87
    bails87 Posts: 12,998
    bomberesque
    I'd agree if the bottom jockey wheel is being pulled towards the front of the frame, it's chainsuck.

    From the OPs description, I'm not sure if that's what's happening though.
    MTB/CX

    "As I said last time, it won't happen again."
  • .blitz
    .blitz Posts: 6,197
    Sticky freehub?
  • nicklouse
    nicklouse Posts: 50,675
    .blitz wrote:
    Sticky freehub?

    I would not say that from the first info given. from the second bit of info i would dismiss it.

    sounds more and more like a worn middle ring.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • tptvmbircn
    tptvmbircn Posts: 782
    thanks everyone, i'll replace the mid ring and check the chain, thinking about it (as i'm currently in work) i broke the chain too so will check the links to see if theres any sticky ones i've got a part worn chain there if i need to do more testing.

    I will post my outcome out of curiosity.

    Terry
  • tptvmbircn
    tptvmbircn Posts: 782
    ok prognosis, correct on the mid ring wear, changed and working great now, but, theres a lovely wide scrath on my newly sprayed frame from the damage so will be touching that up later bad times.