Mountain Bike Reviews Forum banner

bike chain question

901 views 6 replies 5 participants last post by  pimpbot 
#1 ·
I need some advice about a chain problem I'm having. My chain periodically gets caught on the back cog (two of the cogs but not the others) when I pedal the bike. How do I fix this? Is my chain bent somewhere? I'm afraid that my chain might snap when I'm pedaling up hill sooner than later.
 
#2 ·
What do you mean it gets caught in your back cog? Are you running a 10 spd chain on a 8spd drive train or something? I haveno idea what your referring to and would need some more info

First things first...since you seem to think its a problem with your chain...remove it and inspect it. If you don't already have a kmc or SRAM master link, get yourself a favor and use one. Makes life a lot easier.
 
#4 ·
Ok, you know where one chain link links to the other chain link next to it. Normally the teeth of the cog, when pedaling, will fit nicely into the middle of each chain link, but with mine, the tooth hits more of the divider between the chain links, catches a little bit, then snaps into where it suppose to fit nicely into the chain.

It's hard to explain. I should just take it into the LBS, but I don't want to because I don't have the money. I would rather just try and fix it myself.
 
#7 · (Edited)
You might have a bent cog tooth. Carefully inspect it for bent or damaged teeth. Keep in mind, some of the teeth are cut at a bit of an angle to aide in chain pick-up when changing gears. Just look for one or two teeth that are out of line from the rest.

Also, be sure you have the correct chain on the bike, and make sure there are no stiff links. I suggest investing $10 in a chain checker. You can use a ruler to check your chain, but it's a bit trickier. Basically, each link pin will fall on a half inch mark. If it's off by 1/16th of an inch over a couple feet, replace the chain. If you don't care for your chain properly (keep it lubed up well, and don't use degreaser on it), you can actually wear it out in a month and a half. When it wears out, it wears out your chainrings and cogs, and it becomes a lot more expensive to fix.

I'm still unclear on your symptom. So, the chain sucks at the top of the cogset when backpedaling? That can also be caused by a freehub starting to get gummed up. As in, when the wheel spins forwards when rolling down the trail, and your cranks are stopped (coasting) a freehub that isn't spinning freely enough will want to turn the cogset forward, making the top (the driver/tensioned) part of the chain go slack. If you take your rear wheel out, (therefore, isolating the chain from the cogset) you should be able to spin your cogset around pretty freely. While you got it out, make sure there is no bearing slop between the cogs and the rest of the hub.

On reading your posts again, it seems as if the chain is riding between the cogs, is that right? Kinda feels like you're in neutral? I say first check to be sure your derailleur didn't get smacked in sideways. It should be perfectly vertical compared to your chainrings. You can sight down the length of the bike from the derailleur to the big ring. They should be perfectly parallel to each other. Next, check the derailleur adjustment to be sure the chain jumps up and drops down easily with each shifter click.

Check the Park Tool website, too. There are lots of how-to's about diagnosing and fixing issues with your bike, along with maintenance how-to's.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top