First, check your compression, for a stock motor, its supposed to be around 125psi. If its below that, I would definitely consider opening up the top end and checking for cylinder wear, piston wear. If not, go get the cylinder honed, and put new rings in. If its slightly scarred, it must be replaced. I would recommend puttin' in a Wiseco Pro-Lite Piston. Make sure you get the right size. They will run you about $110 with/gaskets. INstad of using the cylinder base gasket, I would go with stock. Anyway, back to subject. If you compression is fine, next thing is to check if the motor has an air leak. If it doesnt, the next thing to go to is Jetting, If you have a STOCK MOTOR, EXHAUST, CARB, AIRBOX, AIR FILTER, or any other stock part that goes to the motor, it should be a #230 main jet, 32.5 pilot jet, 3rd clip on the needle, and 1.5 turns out on a/f screw. If you have any modifications that would effect the motor, just list them all. Example, Exhaust- FMF, air filter- K&N, airbox-factory 7, carb- Mikuni 28mm, Engine Bore (cc), cylinder head. Let us know ALL of it. Better yet, just list everything that is aftermarket on the quad. Hope this helps