chain keeps bunching up... (help)

crabdance · #1 07-12-2008, 09:17 AM

Well last night I tried to start my engine to check and see if a carburetor fix worked. It didn't start on the first time and when I let out the clutch on the second try the back wheels locked up. I carried the bike home on the front wheel, pulled off the clutch cover and had a look. I saw that the chain and bunched up a little left of top center. After working with it for a while, I managed to get it back to the right place again. I didn't take it out again because it was dark by that time.

This morning (a few minutes ago), I took my bike out and wanted to see if it would start and to check my carburetor fix worked. Well, I let out on the clutch to start and you guessed it!... The wheel locked up again. I brought it back home on the front wheel again and opened the clutch face plate. The chain has bunched up in the exact same place as the time before. I tried to move the back tire to force the kink out like last time but it's not working this time. I'm afraid of the amount of force it's going to take to get the kink out.

Has this happened to anyone before? Does anyone know what this means? I would really appreciate any help on this. It's never happened to me before so I don't have any idea of what's going on. Can anyone tell me how to get the kink out other than moving the wheel? How can I stop this from happening again?

Thanks in advance for all the help,
cd

**Ilikeabikea** · #2 07-12-2008, 09:50 AM

It usually takes about as much force to get it out as it did to get it in. As far as not having it happen again. The best way to do that is make sure the sprockets are aligned. Make sure your engine or back wheel are not a little loose. A chain is perfectly happy to run on a sprocket as long as they are aligned. If it gets out of alignment the chain wants to crawl off, and it will...........................

crabdance · #3 07-12-2008, 10:07 AM

Quote:

Originally Posted by Ilikeabikea

It usually takes about as much force to get it out as it did to get it in. As far as not having it happen again. The best way to do that is make sure the sprockets are aligned. Make sure your engine or back wheel are not a little loose. A chain is perfectly happy to run on a sprocket as long as they are aligned. If it gets out of alignment the chain wants to crawl off, and it will...........................

Hi Ilikeabikea, Thanks for getting with me on this. I will check my alignment and make sure that everything is alright there. I just remembered something. Yesterday I had my bike at my neighbors house and the kickstand sunk into the ground and the bike feel over. That might have put the engine out of line some. I will check it to be sure. Although I did ride it several times after that happening with everything working out ok.

Thanks for the help... I will try and see if it's out of alignment.
cd

edit: If it's not the alignment, what else could it be?

crabdance · #4 07-12-2008, 10:18 AM

I quickly checked my alignment and it doesn't look too bad out or anything. I checked the engine and I did notice that it was a little loose. Not much, but a little. When I get the chance today I will tighten that up just in case that has anything to do with it. I have to wonder how much, if any, did my bike falling over have to do with any of this.

thanks for listening,
cd

**Dave31** · #5 07-12-2008, 12:18 PM

How much slack is in your chain? You should have between 1/2 -3/4 of a inch of slack. If your chain is too loose it could cause it to bind up.

http://motorbicycling.com/f3/replace...hain-1139.html

crabdance · #6 07-12-2008, 03:57 PM

ok... I feel dumb but I found out what the problem is. My back rim is bent all to heck. Thats why the chain kept messing up. Now I will have to get me a new rim. The saga continues. At least I know what the problem is now.

Thanks for all the help everyone. I really appreciate it. Now all I have to do is save up the money for a 26 inch rim (have no idea what they cost yet).

cd

**Ilikeabikea** · #7 07-12-2008, 04:43 PM

We have a Salvation Army store and a couple of junk type stores that you can buy an entire bicycle pretty cheap. You might find a complete bike cheaper than just buying a wheel. A bent rear wheel will sure reek havoc with chain alignment. Glad you found the problem......................

crabdance · #8 07-12-2008, 06:12 PM

Thanks man... I will keep my eye out for a used bike. Maybe I can get one for the price of a rim or less.

crabdance · #9 07-14-2008, 11:38 PM

I just got a PM from a nice guy that has a 26 inch rim that he will give me. How's that for a nice guy. I swear the mb people are such good people. Everyone has been so nice to me and helped me so much. I've got a lot to pass along.

cd

jburr36 · #10 07-17-2008, 02:40 PM

Howdy! I had the exact same issue with my bicycle. This was just one of many serious issues I had with my build. Probably more so because on my very first try to start the engine I nearly broke my ankle at the full force of the downward stroke on the pedal. The chain bunched up inside the engine around the sprocket and the casing and locked the wheel up.

After an hour recovering from the sprain I came up with a solution. I formed a couple of 1/2" by 1/8" steel bars around the sprocket. I secured then in place with JB Weld. See attached pics.

I believe this is a design flaw. Also, I have a rear wheel suspension which may have contributed to the chain accident. After I made the modifications I never had an issue with the chain bunching up again.