Have a SunL. 110 Atv. It starts right up, idles great, and seems to be fine. When I accelerate, it makes a loud vibration noise. The tires are good and the chain is snugged up. The engine seems to be swaying back and forth even though both mounting bolts are tight. Any ideas would be appreciated

 

What type of drive system does it have???? belt? if so may check belt or clutch assy.

 

if the chain is to tight it will create a vibration

 

It's chain driven. I got it running after cleaning out the carb. I also tightened the chain while I was tinkering with it. I will try loosening the chain and see what happens. When it vibrates, it makes a loud noise almost like an aggressive tire would make in a truck.

 

Is it an auto or foot shift?

 

It is auto

 

I loosened the chain a bit and same problem still exists. Any other ideas?

 

The chinese atvs tend to have vibration. The engine is bolted into the chassis without any engine mounts, direct bolt on.

Its some of the culprits of chinese atvs, my kids complain about it. Make sure you locktyte all nuts and bolts, and if possible isolate the cdi, rectifier with rubber grommets, or velcro straps.

 

The sunL brand looks identical to my gio.. No vibrations at all. Only time i had vibration/noise is when i put new chain and sprockets on. Tolerances are not perfect on imports so the sprockets are a little off center. So depending on where you set your chain tightens it could be tight until it makes 1/2 a rotation or so and gets to the offset part of the sprocket then they get super tight. On mine when the chain is at its loosest section it actually hits the frame but the tightest part their is no play in the chain.
with your engine moving i would almost say that is the issue. see if your engine sway goes with the movement of the tires

 

Ive got a 125 Jetmoto that vibrates pretty good also.. problem is like crankestein said.. the engine is only mounted with 2 bolts.. its not enough.. best fix would be to add a motor mount under the engine.

Mine is ridden by my daughter in law and she doesnt go fast enough to notice or care about it.