i have not ridden dirtbikes since 2000 so this new fourstroke technology is all new to me. I have been breaking it in according to t he manual and what i notice is t hat when ur accelerating it backfires alot and seems hesitant and dead untill tyou get on the throttle.. i called the dealer and they said they put regular gas it it so i took it home drained it and put in premium. i rode yesterday and it deffinitly ran better but still backfires while accelerating and im just not sure exactly how its supposed to run and sound when bran new.