I am going to look at a 2005 YZ250 this evening. I did look at it Saturday and I'm going back for a 2nd look. From my memory, the kicker wasn't curved which would indicate on older model. To tell the truth, I wasn't really focused that day, or didn't really think much of it, so I'm not really sure what I saw. Is there anything else to look for on the motor that would indicate year? Are the kickers interchangeable? Motor is supposed to have been fully rebuilt with Eric Gorr porting and some head work. So not bad-if I can see the receipts.