I bought a brand new Coolster 125cc Atv from a guy that buys the parts then has his crew put them together, so far we have had this happen to it...
Right shock broke
front tires had 10, 35 pound of air (should only have like 20)
back tires 25, and 55!!
both back tires sprung a leak
left headlight don't work on dim
needed carb cleaned
we have only had it for like 2 months and all this has happened to it, is that normal??
now the Barring (i think) is broke,and i have to put the chain on like 5 times a day, can only turn right, if you turn left the chain falls off, i will get pics in a bit but for now any suggestions??

 

wow, did the guy hire teenagers to put them together? sounds like they obviously did not do a good job. assembling the quads is a fairly easy task and shouldn't have been that bad.
did you mean bearing? like, rear axle bearing? i'm going to PM you a manual that's fairly generic and has some good information in it that may apply to your quad. what kind of warranty did he give you? does the rear axle wobble a lot to make you think the bearings are out?