Forum home Mountain biking forum MTB workshop & tech

Chain Pinching

nik1978nik1978 Posts: 3
edited November 2012 in MTB workshop & tech
Hey Guys, first time poster, have searched the forum but couldn't find a problem like mine, hopefully someone might be able to give me some advice and get this fixed.

I have a 08 Specialized Enduro S-Works and over the last few months I've been getting a strange issue which my LBS don't seem to be able to fix as they can't recreate it in the workshop.

When riding in wet and muddy conditions (this mainly happens in the small chain wheel) the chain will jump off the chain wheel (towards the frame) and get pinched between the small chain wheel and the mounting bolts of the front mech. This locks the chain and nearly pitches me over the bars when I'm tackling an energetic uphill.

Prior to these pinches the bike is running normally, no grinding or rubbing in the gears. When a lockup is approaching, in the few seconds before it does, I'll hear a little ticking or grinding noise and then it'll lockup.

It seems to be also linked to me being on the bike as it doesn't happen when we're spinning the gears on the trail trying to see what happened. It always happens when I am climbing in the saddle.

My chain has been measured and apparently its ok for wear.
I've checked the teeth on my sprockets and chain wheels and they all look low wear and not bent.

Am running Shimano XTR on the front and rear mech's

Any ideas? As it only happens on a wet or muddy ride, the LBS can't recreate it in the workshop

Cheers for any answers or advice

Nik

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    chain suck. have a read http://www.fagan.co.za/Bikes/Csuck/

    and then have a think about what to replace.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • I'm not entirely sure it is chain suck if I'm honest... the chain isn't failing to disengage from the chain wheel like traditional chain suck. I've done a bit of googling and read about chain suck beforehand and didn't think it totally fitted the bill as the reason.

    I shall look into it though.
Sign In or Register to comment.