Its pretty close to Yamaha660R's answer.

Its definitely not the 1:1 ratio, because I took off 58 lbs from my raptor and its not that its 118hp bike now but it did make a big difference.

 

When you put the engine into anything you are loosing horsepower through drivetrain inefficiencies .. the engine is still creating the same HP, it's just having to go through gears/belts/shafts and/or chains and bearings to get to the ground where it is needed.

If I thought I could gain 1hp for every pound I shaved off my Warrior I'd be gettin out the torch pretty quick!! [img]i/expressions/face-icon-small-happy.gif[/img]
95Wolverine got it right .. it only affects the "apparent" horsepower ... that's why weight savings are so important .. power/weight ratio is a big factor in the performance of any machine.

 

Think of it this way. By taking the weight of a vehicle and its quarter mile time you can work an equation and get a measure of HP. By lowering a vehicles weight it will be faster and if you calculate its hp using its old wieght it will come out to have more hp. Ofcourse you have to change the equation since it now weighs less but compared to how it was before its like you gained hp. There is really no correlation between weight of the bike and hp, its just to give a tangible speed representation to how much losing a certain amount of weight would help "If we could shave 70lbs off of this bike it would be the same as gaining ~10hp!".

 

That's the difference between flywheel horsepower and rear wheel horsepower, where there is parasitic loss through the drivetrain.

 

weight loss= more speed, not more horsepower

 

I asked this question awhile back and all I heard was to many variables. [img]i/expressions/face-icon-small-disgusted.gif[/img] Now everyone is all over it this time. [img]i/expressions/face-icon-small-sad.gif[/img] You are leaving out torque [img]i/expressions/face-icon-small-confused.gif[/img] I see how it is.

 

Lets make this simple. Strap a 5hp motor to an anvil with wheels, then strap it to a 2x4 with wheels. Which one is faster? the 2x4. They both have the same hp. The anvil woluld need like 20hp to keep up so if you shaved the anvil down to a little bar that weighed the same as the 2x4 you could say the anvil had done the same thing as gained 15 hp.

 

Cool, so all I have to do is shave my anvil (Warrior) down to a sliver and the apparent gain would have me whoopin 450's [img]i/expressions/face-icon-small-happy.gif[/img]

'course i'd have nothin to sit on [img]i/expressions/face-icon-small-shocked.gif[/img]

LOL .. these topics are funny [img]i/expressions/face-icon-small-smile.gif[/img]

 

Or you could build a super lite frame/swing arm/a-arms, get super light wheels tires and axle, run no battery, a tiny gas tank, no plastic, and get a 70lb kid to ride it. Then it would be blazin fast [img]i/expressions/face-icon-small-smile.gif[/img]

 

Exactly, that is what I assumed everyone knew when I said that it's more like 7-10lbs for every 1hp. I didn't mean, nor did I think anyone wasw believing you add hp by dropping weight. But you get faster when your lighter. The lighter the bike the better your power to weigth ratio is.