I've now had a odd and disturbing noise during startup two times. Both times the bike had not been started for a couple of weeks. Both times the bike was on the center stand and in neutral. Depress starter, bike starts to turn over, then I hear what sound to me like a metallic 'thwack' and the engine turn over just knocks off and dies. Sounds to my untrained ear like something came lose of hit something. If I were sitting on the bike, sounds like it comes from the right hand side of the bike in the engine area. Anyhow, afterwards, have to feather the throttle to get bike to turnover and start. Subsequent startups seem normal. Anyone expereince something like this before? My dealer says it's not a 'dangerous' sounding noise, but I am concerned. Bike is under warranty tho.