chain suck

[jon gaper]

this has happened before,but never this bad. this is an iron horse all-mtn race with only 500 miles . the chain was so wedged in beneath the pivot that i had to break a link and loosen the inner chain ring and bang the chain out with a screwdriver and hammer. i didnt have a crank removal tool with me.there has to be an easier way 1) to avoid this 2) get the damn chain unstuck. HELP! i would hate for this to happen 20 miles from nowhere. thanks.

[Froman]

Make sure your chain is lubed.

[jon gaper]

the funny thing is that i just lubed it....

[LaBelle23]

Were you on the bike when you changed gears? I got a chain wedged that bad when I was changing gears and not even on the bike.

[mntlion]

chain line OK?
chain rings, chain and cass all not worn out?
clean (not just lubed) chain?

[uncle crud]

Every time I've had chain suck it was from sticky, gritty mud on the chain.

Every time.

Not saying that's what is causing yours.

Just saying.

[DH-Roach]

it could be that your getting chain slap, and then chein suck. try taking a few links out of the chain. put in 1st on your cassette and 3rd on your chain rings, to make sure that its not too tight. you still want a little bit of give in in so you don't tear up your cassette and derailer. maybe a stiffin up the tension screw in your rear derailer. if that doesn't work idk.

[jon gaper]

i was going from flat to a slight hill shifting the big ring to the 2nd while applying some pressure out of the saddle. the chain was lubed, no mud , but not shiny clean. the rings and chain only have 500 miles.the length had been ok just before this. what amazed me was how DAMN hard it got wedged , especially since i noticed it right away. do those anti-chain suck devices work? i was just lucky to be near the trailhead this time. i think the rear pivot made it so difficult to get it unstuck.

[1wsguy]

Is this a chronic problem with this current set up that you have, or just happened this time?
Check for a bent tooth on your chainrings, or a twisted or otherwise failing link in the chain.

[uncle crud]

i was going from flat to a slight hill shifting the big ring to the 2nd while applying some pressure out of the saddle.

There's your problem.

Shift the front der under very mild light spinning tension. NEVER under load, and definitely not while standing, pedaling up a climb.

If you drive a manual transmission car, then here's a good analogy for you.

Shifting your bike's derailleurs while under pedaling loads is like trying to shift gears without using the clutch. You might get it right if you time everything perfectly and the synchronizers in the transmission are your best friends, but otherwise you're just asking too much of the mechanical system.

[pechelman]

2nd'd what UC said above

but everytime Ive had chain suck was on a bike that had a bad chain line or crappy rings or something. Its really only been on one bike, and since I swapped the stock BB, chain, cranks, and rings, for fancy ones, the problem instantenously went away. And yes everything was clean and lubed in both scenarios.

The problem was so bad I ended up making my own chain suck gaurd. Looked like 2 plates of aluminum, hole drilled in the center of both to clamp. Larger peice was machined to match the chainring profile and be butted up pretty closely to the rings, thus not allowing any room for said chain to get sucked.

[jon gaper]

there was a sticky link after removing the chain, but maybe that was caused by the wedging . now, would you trust a repaired chain or replace it?

[jibco]

Shimano chain? Trash it.

Otherwise, it depends on how good you can repair the chain.

[1wsguy]

Remove the bad link and shorten the chain (if you can), or replace the bad link with some sort of quick link (kmc missing link or other).
One more thing, make sure you don't have any loose chain ring bolts, I've seen loose or missing bolts cause some similar problems.