You probably need to take the carbs apart and clean them, then just so you know, the petcock on the Yamaha doesn´t have an OFF position...it has ON, PRIme and REServe and when you´re trying to start it, put it in the PRIme position. Remove the seat and spray some starting fluid in and see if it´ll fire up, the gas when it´s not on PRI is drawn with vaccuum. It handles fine but an inline four is alot quicker than a V-twin...so when you crack the throttle in a turn be aware of the physics involved. The only problem I´ve had is in a long lean to the right; starves it for fuel. Respect it´s power!