my buddy across the street has a beautiful 2009 yz450f, which he bought from my buddy (a mechanic in Alberta) a few months back. bike has hot cams , high compression piston, dr d exhaust and I don't know what else. runs like a damn champ ill tell ya that. he just put a new tire on so he was out alllllll day yesterday and never had a problem. this morning he wakes up, goes out to kick her over and she starts for about 3 seconds then just shuts off. what could this be? jet stuck open and flooding carb possibly??