Hello, CRF 450 rider here... I love open desert riding, and i think the CRF 450 is a little under powered? i mean.. it hauls ass, but i think i would want something bigger for my open desert riding/racing.. and i hate switching out sprokets,,, I few simple 650 Q's: What do they usually go for... price wise.. for one that is a few years old.. example.. 02-04... any years i should avoid?? what years are the best... Any major valve issues like the 450?? THANKS A lot.. i really appriciate any information!!