Well after reading the problems with these china quads, i thought i would let you know i have had the same problems.
If i was not mechanicaly minded it wouls have been ramed back where the seller would not like it.
These Quads come with faults, fualt and more faults.
I purchased a 110cc quad, when it turned up parts were missing, tyres would not pump up.
You fill the fuel tank up and it runs out the carby as quick as you put fuel in from the overflow with not needle and seat fitted.
try to start it and battery is flat si i try and charge battery will not charge or hold charge, so you ring the seller and the best they can do i send a repacement @ a cost as the battery is not covered.
once i get it going the brakes don't work, so email after email and i finaly get a phone number to ring and arrange some parts, great something covered and new part on the way, but when they get here they are different and dont fit, there are so many models the cant seem to get the right parts to you.
Take it from me they are not worth the MONEY, GO TO YOU LOCAL DEALER AND BUY ONE THAT IS A BRAND, E.G. HONDA, YAMAHA, WHAT EVER.
you will be able to go back and get some service and a warranty.
cheers if you buy one of these bike dont say you were not TOLD