Most of the nitty gritty detailed specs for the Yamaha YZF-R3 can be found on Yamaha’s website here:
http://www.yamahamotorsports.com/sport/products/modelspecs/718/0/specs.aspx

I have completed my comprehensive power testing on the Yamaha R3 and the results are available here:

Yamaha R3 Dyno Results, Exhaust and Fuel Controller Testing

There hasn’t been any official release of US model power output, but the European version is rated at 42 horsepower and 21.8 pound-feet of torque at the crank.  Cycleworld did a dyno test and recorded 36.8 horsepower and 19.2 ft/lbs of torque.  The full results and video can be found here:

Cycleworld.com Dyno Results 2015 Yamaha YZF-R3

For comparison, here are the similar bikes and their output (all of these ratings are output at the crank and will be similarly less at the rear wheel):

Yamaha R3 Specs

There has finally been a pretty good overall review of the new small bike competitors done by the well respected, lap record holding, seasoned racer, Ari Henning:

View the whole review here:

2015 SMALL SPORTBIKE SHOOTOUT | ON TWO WHEELS

Yamaha R3 Chuckwalla

Yamaha YZF-R3
42 hp @ 10,750 rpm
21.18 lb ft @ 9,000
Wet Weight 368 lbs
Power to Weight Ratio (bike only)= .114 hp/lb
Power to Weight Ratio (w/ 180lb rider)= .077 hp/lb

Ninja 300 vs Yamaha R3

Kawasaki Ninja 300R
38.89 hp @ 11,000 rpm
19.91 lb ft @ 10,000 rpm
Wet Weight 383 lbs
Power to Weight Ratio (bike only)= .102 hp/lb
Power to Weight Ratio (w/ 180lb rider)= .069 hp/lb

Ninja 250 vs Yamaha R3

Kawasaki Ninja 250R
31.51 hp @ 11,000 rpm
13.6 lb ft @ 9,750 rpm
Wet Weight 375 lbs
Power to Weight Ratio (bike only)= .084 hp/lb
Power to Weight Ratio (w/ 180lb rider)= .057 hp/lb

Honda CBR300 vs Yamaha R3

Honda CBR300R
30.5 hp @ 8,500 rpm
20 lb ft @ 7,500 rpm
Wet Weight 364 lbs
Power to Weight Ratio (bike only)= .084 hp/lb
Power to Weight Ratio (w/ 180lb rider)= .056 hp/lb

Honda CBR250 vs Yamaha R3

Honda CBR250R
23.7 hp @ 9,900 rpm
12.7 lb ft @ 7,400 rpm
Wet Weight 357 lbs
Power to Weight Ratio (bike only)= .066 hp/lb
Power to Weight Ratio (w/ 180lb rider)= .044 hp/lb

KTM RC390 vs Yamaha R3

KTM RC390
43 hp @ 9,500 rpm
25.8 lb ft @ 7,250 rpm
Wet Weight 340 lbs
Power to Weight Ratio (bike only)= .126 hp/lb
Power to Weight Ratio (w/ 180lb rider)= .083 hp/lb