I have had this 01 YZ 250F for one year. Just after I got it, I had the valves re-shimed (they were.012in off). Even after I got that done it was real hard to start. Just before I put it up for the winter, the pilot jet screw vibrated out so I put it back in. When I started it back up it would die everytime I gave it gas so I continued to turn it out until it ran good (7-8 full turns). but then the exhaust header got real real red with in 5 minutes of idle. Like cherry red hot. I just put a new jet screw and spark plug in and cannot get it started. I don't think I have enough compression because i can kick it without using the decompression lever. so I think I may have bent a valve when the header was gettin red. Any tips or advice would be helpful. Thanks.