# Power to Weight

Power to Weight Ratio: How much weight that the engine and gears has to push has a huge effect on your performance. For a given bike, the lighter the load, the quicker you can go and the gears can be taller. My '05 600RR weighs 422 lbs with a full tank of gas and no rider on board (50.5 %F, 49.5 %R), With me and gear on the bike, it weighs 635 lbs (46.4 %F, 53 %R). A different rider may bring that total weight down to 600 lbs, a 35 lb difference. this could be the difference of one tooth on the rear sprockets with the same accelleration and a higher top speed.

Lets use Horsepower to understand this: (550 Ft*Lb/Sec. = 745.7 Watt = 1 HP) Pete & 600RR - 635 Lb / 101.4 HP= 6.26 Lb / HP Light Rider & 600RR - 600 Lb / 101.4 HP = 5.92 Lb / HP or Pete & 600RR - 101.4 HP * 550 Ft*Lb/Sec. / 635 Lb = 87.82 Ft / Sec Light Rider & 600RR - 101.4 HP * 550 Ft*Lb/Sec. / 600 Lb = 92.95 Ft / Sec or Pete & 600RR - 101.4 HP * 745.7 Watt. / 635 Lb = 119.1 Watt / lb Light Rider & 600RR - 101.4 HP * 745 Watt. / 600 Lb = 126.0 Watt / lb

Lets use Torque to understand this:

Pete & 600RR - 41.8 Ft * Lb / 635 Lb = 0.66 Ft. Light Rider & 600RR - 41.8 Ft * Lb / 600 Lb = Ft.

Lets use Driving Thrust to understand this: (Peak, 2nd Gear)

Pete & 600RR - 519 Lb / 635 Lb =0 .817 Light Rider & 600RR - 519 Lb / 600 Lb =0 .865

Clearly, by using Horsepower, we can obtain comparable units that mean something to us. This is about the only reason to use horsepower numbers.