Chain won't line up to the Drive Sprocket

Ryno

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I have everything put together on my first build here. I'm running a 48cc Grubee Skyhawk.

Initially, the chain wouldn't line up on the rear wheel sprocket. The chain would fall off when it was rolling. I got that "straightened out". The rear wheel sprocket is now as close to the spokes as it can be while still clearing the chain.

Now, when my bike is rolling for a little bit the chain falls off of the front drive sprocket in the engine. It falls off to the left of the sprocket.

It seems that my engine may be on a strange angle, and the chain is not lining up with the sprocket correctly. However, it's mounted on the bike right where it should be.


I was thinking that the bike frame itself may be bent somewhat, so that the rear wheel doesn't line up correctly.

What do you think the problem is, and how can I fix it?
 
Okay, multiple questions here.

* How are you mounting the sprocket to the rear wheel?

* How much slack is on the chain?

* Are you using a chain tensioner/idler pulley?

* If so, how is it installed?
 
First it was mounted just as suggested, with the rubber parts on the inside and outside. But that didn't work because the chain would pop off of the back sprocket, even when it was straight. The person helping me had his set up a certain way, so I copied it. This is how it is:

the dish side is IN, and there is no rubber part on the outside of the wheel. There is enough room for the chain to clear the spokes.

The chain does not have a lot of slack, but it's not pulled tight either. It seems to be a reasonable amount, but there might be too much.

I'm using a chain tightener just the way it's supposed to be used.

I can post a picture later
 
First it was mounted just as suggested, with the rubber parts on the inside and outside. But that didn't work because the chain would pop off of the back sprocket, even when it was straight. The person helping me had his set up a certain way, so I copied it. This is how it is:

the dish side is IN, (you mean that looking at the sprocket from the left side it looks like a dish?) and there is no rubber part on the outside of the wheel. There is enough room for the chain to clear the spokes. Rubber rag joint installed up against the spokes on both sides, 3 washer plates on the inside of the wheel up against the rubber, and sprocket against rag joint on the outside.Have you beveled each tooth on both sides of the sprocket?

The chain does not have a lot of slack, but it's not pulled tight either. It seems to be a reasonable amount, but there might be too much.

I'm using a chain tightener just the way it's supposed to be used.

I can post a picture later
I had a chain that was popping off the wheel sprocket and caught between the sprocket and spokes. The gear teeth were the furthest away from the spokes that would allow. What was causing it was that the chain was hitting the frame just enough to derail from the sprocket...a added washer just inside the frame where the axle fits solved the problem.
 
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Are you suggesting that this could solve my problem?

I suppose an added washer for the axel could move the wheel over just enough to line the chain up correctly with the drive sprocket.
 
"Rubber rag joint installed up against the spokes on both sides, 3 washer plates on the inside of the wheel up against the rubber, and sprocket against rag joint on the outside."

I know that this is how it is supposed to go, but the chain would not line up with the back sprocket when it was set up like this.

The person helping me has his set up like mine and his works just fine.

As for 'beveling each tooth", no I haven't.
 
Are you suggesting that this could solve my problem?

I suppose an added washer for the axel could move the wheel over just enough to line the chain up correctly with the drive sprocket.
I had to do that to mine and it works fine...can't tell when riding it other then the chain stays put. Is the engine mounted CORRECTLY???

http://s982.photobucket.com/albums/ae309/Ron-Becker/Engine%20Mounting/
 
"Rubber rag joint installed up against the spokes on both sides, 3 washer plates on the inside of the wheel up against the rubber, and sprocket against rag joint on the outside."

I know that this is how it is supposed to go, but the chain would not line up with the back sprocket when it was set up like this.

The person helping me has his set up like mine and his works just fine.Are you using the same exact setup....Bikes, sprocket etc? EVERYTHING

As for 'beveling each tooth", no I haven't.
.........
 
Looking at the bike from the rear, is the sprocket to the left or the right of the motor's drive sprocket?

And when you say the dished side is in, is the chromed side out, or in?

Just for extra clarification between now and when we get pictures.
 
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