Dynos are all different. I'd like to see Cycle World do a full test so we can get comparable weight and power numbers on this new guy. Meanwhile, here's one take:
Originally Posted by bryantjt
A16tony has had both on a dyno, a piped/jetted KLX put out 21 hp and his new WRR put out 24.9 stock. Stock the KLX was 17. A 331cc, pumper carbed, piped/jetted KLX puts 28 hp to the wheel (Nobrakes' bike).
The YZF-R1 engine on which the WR250R is based puts out 157.1 horsepower at 12,200 rpm (Cycle World, August 2007) so theoretically in the same tune the WR250R would be capable of producing a fourth of that, or 39.3 horsepower!
The WR250 is running less compression and has a lower redline. The exhaust is probably more restrictive. It might have altered cam timing as well. Even so, 25-30 hp is no stretch.
Oh, and my calculations show 99 mph at 10,000 rpm in 6th gear.