chain problem

[cab32]

HI
Put together an ATA-250D this week. runs well but the drive chain comes off the sprocket frequently. The front and rear sprockets are aligned well and all bolts tightened down with the chain tight. There is a chain tension pully.Has anyone had this problem or any suggestions to prevent the chain from falling off. of course the owners manual says nothing about adjusting the chain but I have used Honda CB's for years so I know how a chain drive is made to work but this one has me confused. I notice that the rear shock coil seems weak. It depresses easily and returns to preload height very slowly compared to a motorcycle. Could this be part of the problem? CAB

[VinceDrake]

I Can't speak for that specific model, but the rear swing arm bushings sucked completely on Both My ATV's. Just a crappy little rubber bushing, with a hunk of pipe through it. Woo!

What would happen, especially on the 200 (Very similar) When you'd hammer on it, or crank it around a corner, the rear swing arm bushings would flex enough to run the sprockets out of line,resulting ina dropped chain. Tightening the crapola out of the rear swingarm pivot helped for a while, but I eventually ended up making a set of Bonze bushings out of some old Transmission bushing kits I had lying around.

Also-- The swing arm itself was very flex-y. Ended up brazing in some cross-braces to make it a little bit more structural.

Couple things to check out...

--Vince

[cab32]

Thanks. that makes sense. My swing arm bushings are just rubber. I will tightne them and If it helps will look into using bronze bushings. I wonder if there are any other posibilities. CAB

[VinceDrake]

Oh Yeah! I almost forgot-- The sprocket on the 250 was loose from the axle when I got it. Wobbled lots, and dropped chain repetitvely.

As for the bushings, I was originally going to use a couple of front bearings from a GM SI-series alternator (with some help from my trusty die-grinder) But thought maybe they wouldn;t like the impact too much...

--Vince

[warrior91]

I machined bronze bushings for my MIC bikes after the first tank of fuel!
I think Vinnie D has hit the nail on the head. :!:
The pipe/rubber separates or goes out of round... But for a couple hundred dollar bike some upgrades are necc.

[VinceDrake]

Us Saskachefarm people got it goin' on! :)

--Vince