hi guys, i recently purchased a 07 yz 450. just wondering if anyone else has had any problems with timing chain skipping and oil feed problems. at 11hours a high pitched tick started in the engine, had the valve clerances checked all ok. at 30 hours, noise increased in 1 ride to louder then the exhaust. sent it to the dealership, cam chain has stuffed the crank and cams, the buckets are worn in the head, and the oil pump drive has worn into the clutch basket, so i am basically up for a whole engine with the parts list i have been given. yamaha wont cover it. thanks.