Good evening folks. I am new here as I just bought my son a 90cc chinese atv. I do not even know which brand it is (it does not say it anywhere that I have found). The decals on the plastic say atv-109b. Anyway, He's been riding it incident free for the last 2 days, but tonight, the chain popped off on him twice. There is quite a bit of play in it and I was just wondering if there is some way to adjust the tension. Any help you can afford the newbie would be greatly appreciated. Thanks!

 

Did a yahoo search on the atv-109b. Looks like it's a Sunl quad.

As far as the chain, there are bolts on the back axle that you loosen for adjusting the chain tension. The bolts for the adjustment probably loosened up allowing the axle to move forward toward the engine allowing the chain to get slack in it. Different quads have different mounting hardware, but the axle should have a slotted place with bolts through them where the adjustment is made. Loosen these bolts, force the axle back to take out the slack and then retighten the bolts.

 

One other thing to check for: I've read where the motor mount bolts loosen up and allow the motor to shift in the frame. Might wanna check these too. They can be reached from the underside of the quad.

 

thanks for the help!