I recently got a yfz450 and was told had not been run in at least 1 1/2 years  well after new oil and gas (which was not drained) i drained added new gas and with a little help from carb cleaner it started but would not take throttle would just die now seems like has to much compresion and wont turn over enough to start i dont think they had the valves adjusted  could that be the problem   if you have the time please help   thanks