I spent last weekend riding at Hollister. Out of our large sized group one had a 2002 XR650R and one had a 2005 CRF450X. I raced both of them at different times. The races were short because of room and we stopped at approximately 65 mph. Both races were also started in 2nd gear. For the record, my 2006 WR450X has the free mods, JD jetting kit with blue needle in 3rd position, 45 pilot, 168 main, UNI filter and Pro Moto Billet exhaust insert: vs CRF450X (exhaust baffle removed, pink wire mod NOT done): he hit it first, when I hit it I consistently pulled away from him at all rpm ranges, when I let off I had several bike lengths on him vs XR650R (uncorked, 13 tooth front sprocket, UNI filter, "E" series pipe with 12 discs and quiet core insert, 68s pilot and 178 main): closer than the 450X but the WR clearly had a power advantange. My friend said when I started hitting the higher rpms then I pulled away even faster from him. I don't know what the approximate distance in bike lengths was when I let off. I said this before, I do believe my WR450 is faster than my XR650R before I put a cam and pumper carb in it (650). I love the WR more and more each ride. I had been considering installing the YZ cam but I've decided to upgrade the seat and tank in preparation for my next desert trip.