04 CRF 450, 80 hrs run on MX tracks and some playriding, very well maintained, valves in spec. "C" rider, Tires in great shape and right for surface ridden. Seems to me that I used to be able to loft the front wheel to manual over small kickers or entering whoops, with just leaning back a little in second thru fourth. Now it takes being in the thickest part of the band and a good yank in only 2nd or 3rd. Still has a good mid-range kick but it seems to be milder than before. Low end feels sluggish. Should I get a compression test to tell if I need new top end? Or should I inspect cylinder and piston because it may just need rings? Or if it looks pretty good in there, maybe I need a Hot Cam Stage One or a higher compression piston (that doesn't need race gas)? Help!