The uncorked XR650R has significantly more total power in terms of torque than the stock race ready CRF450R, but they have very similar power to weight ratios and that's very important, especially on tighter courses. An uncorked XR650R produces close to 42 lb/ft of torque at 5,500 RPM and close to 48 rear wheel HP at 6,500 RPM. The CRF450 comes stock as a full fledged race bike and produces about 29.5 lb/ft of torque at 6,500 RPM and 40 rear wheel HP at 8,000 RPM. The CRF450 has a much broader powerband that's very linear and it will keep pulling where the XR650R falls off in the RPM range, so naturally it will feel faster to some people. Gearing also plays a big role in all of this. A modified CRF450R that includes a special cam grind that's installed to the correct degree with higher performance valve springs, retainers, guides, porting, 12:5.1 piston, power now valve, Doma exhaust and running Nutec Special 5 fuel produces about 34.7 lb/ft of torque 7,200 RPM and about 53.4 rear wheel HP at 9,200 RPM. Now if you modify the XR650R with a 680 kit, cam, piston, header & exhaust, you can boost the torque to about 50 lb/ft at 6,000 RPM and raise the rear wheel HP to 64 at 7,500 RPM. If you take the total torque of the bikes and divide it by the weight of the bikes, you'll get a better idea of the power to weight ratios. CRF450R @ 29.5 / 225 = 0.1311 lb/ft torque per lb of bike weight. CRF450R modified @ 34.7 / 225 = 0.1542 ft/lbs torque per lb of bike weight. XR650R @ 42 / 277 = 0.1515 lb/ft torque per lb of bike weight. XR650R modified @ 50 / 277 = 0.1805 lb/ft torque per lb of bike weight. You can clearly see that an uncorked XR650R engine still makes more raw torque than a stock CRF450R and it's very closely matched to a modified CRF450R in terms of total engine torque, but an uncorked XR650R makes its power with more reliability, with less effort, thus less with maintenance. When you modify the XR650R with the 680 kit and other goodies, then the choice becomes very clear, especially on courses where weight isn't an issue. No matter how you slice it, the CRF450R is a very attractive bike and extremely competitive due to its lighter weight, but the XR650R is still very competitive when the weight of the bike isn't as much of a factor. Gary, Resident BRP Einstien I found this on www.xr650r.us thought it was very interesting.