trouble with rear sprocket/chain

brucemg51 · #1 08-02-2008, 07:59 PM

I've spent the better part of a day aligning the chain with the front and rear sprockets and making sure the chain isn't rubbing on the frame or tire. But, the chain doesn't seem to want to mesh smoothly with the rear sprocket. It keeps binding up and coming off the sprocket. It makes a lot of noise even when it does manage to stay on for a while. Any hints as to how to smooth it out?

**Bikeguy Joe** · #2 08-02-2008, 08:23 PM

See if the tips of the teeth are catching the chain. Some older kits had this problem. The way around it is to take the rear sprocket off and file or dremel the edges of the teeth off. Not a big deal.

brucemg51 · #3 08-02-2008, 09:18 PM

Quote:

Originally Posted by Bikeguy Joe

See if the tips of the teeth are catching the chain. Some older kits had this problem. The way around it is to take the rear sprocket off and file or dremel the edges of the teeth off. Not a big deal.

Not sure what you mean. Is catching the chain a good thing or a bad thing? File the edges of the teeth so they are narrower?

NunyaBidness · #4 08-02-2008, 10:28 PM

Quote:

Originally Posted by brucemg51

Not sure what you mean. Is catching the chain a good thing or a bad thing? File the edges of the teeth so they are narrower?

yeah, just knock the square edges of the teeth off, on both side, and this will allow the chain to meet the sprocket better
good luck

jasonh · #5 08-02-2008, 11:18 PM

Here's one thing I noticed today. If your rear chainstay is angled outwards as it goes back towards the wheel, you may have issues. The tensioner will be at the same angle of the chainstay, and this makes the chain run at an angle across the tensioner wheel. If you adjust it so it's quiet, it takes the chain off the sprocket.

One solution would be to "twist" the bracket. I tried to do it with a couple pair of pliers today but failed. Need to figure out a good way to do it.

Andyinchville1 · #6 08-03-2008, 12:36 AM

HI jasonh,

To bend the tensioner bracket it really helps to have a table mounted vise and a large pipe wrench and/or a small sledge hammer....Pliers may work but you'd probably have to look like Rambo to do it using that ;-)

Hope this helps you....Good luck!

Andrew

PS - 2 pipe wrenches may work tho....just need the longer ones for more leverage....

**Bikeguy Joe** · #7 08-03-2008, 07:51 AM

Quote:

Originally Posted by jasonh

Here's one thing I noticed today. If your rear chainstay is angled outwards as it goes back towards the wheel, you may have issues. The tensioner will be at the same angle of the chainstay, and this makes the chain run at an angle across the tensioner wheel. If you adjust it so it's quiet, it takes the chain off the sprocket.

One solution would be to "twist" the bracket. I tried to do it with a couple pair of pliers today but failed. Need to figure out a good way to do it.

I "adjust" mine with a pair of 18" channel lock pliers.

brucemg51 · #8 08-03-2008, 08:41 AM

Quote:

Originally Posted by jasonh

Here's one thing I noticed today. If your rear chainstay is angled outwards as it goes back towards the wheel, you may have issues. The tensioner will be at the same angle of the chainstay, and this makes the chain run at an angle across the tensioner wheel. If you adjust it so it's quiet, it takes the chain off the sprocket.

One solution would be to "twist" the bracket. I tried to do it with a couple pair of pliers today but failed. Need to figure out a good way to do it.

What is "rear chainstay"? Is this different from the tensioner? Am I missing something?

Andyinchville1 · #9 08-03-2008, 09:48 AM

Hi,

The rear chain stay is the piece of the frame that you typically mount the chain tensioner on....It is the tube that runs parallel to the ground from the bottom bracket to where the rear wheel attaches to the frame.

Hope this helps

Andrew

brucemg51 · #10 08-03-2008, 09:52 AM

Quote:

Originally Posted by Andyinchville1

Hi,

The rear chain stay is the piece of the frame that you typically mount the chain tensioner on....It is the tube that runs parallel to the ground from the bottom bracket to where the rear wheel attaches to the frame.

Hope this helps

Andrew

Thanks. Being an old motorcycle mechanic, I would think of that piece as the swingarm, although the term doesn't really apply to a bicycle.