So now that I'm getting into this whole thing with hooking up my new raptor, I was told by this guy yesterday that with Dirt bikes and quads , if you remove or replace weight from the machine you gain horse power. I can see this being SOMEWHAT true because that would mean less weight = less energy required to move the machine. But he claims that it's almost a 1:1 ratio. Or for every pound lost = 1 hp gained. Is there anyone who can back up his statement? I know that in Drag Racing (automobiles) That if you remove weight rom the wheel's (ie.steel to aluminum) that you get a power gain because of the unsprung weight difference. Where are the engineers out there?? Cause I'm sure we would all like to know.

 

when your sitting on it and if ur a big guy youll hold it down, but it will not effect your hp..it just puts more strain on the engine making it harder to pull you around. So if by removing weight its obviously easier for the engine to pull you around

 

That is BS. So if you took off 10 lbs you get 10 more HP.

 

well that was my thinking too that there has to also be a limit somwhere in the equation and it cant even be clost to 1:1 ratio. but there might be some possibility that by removing weight here and there can add up, and some power might be gained somewhere. with rider weight NOT BEING A FACTOR, Just machine.

 

I don't buy this theory of 1:1 either.

Your engine makes a certain amount of horsepower....There is no changing that unless you mod the engine in some way, shape, or form. So, we'll stick to our engine as it is.

Now, if lets just for fun say you are making 40HP. We will not change this engine, so no matter what we do the the weight of the bike or the rider, the HP form the engine stays the same.

Now, lets just for fun say the bike weighs 400 lbs. The Horsepower to Weight Ratio would be 1:10.
Now, if you were to add 10 lbs to the bike, it should feel as if you lost 1 HP. Keep in mind that it only feels that way. Your bike is still making the same HP.

Now if you were able to reduce the weight by 10 lbs, it would feel as if you gained 1 HP. Again, it only feels this way.

For your friends 1:1 ratio to hold true, you would have to 1 HP for evey 1 lb of machine. I have yet to see a 400HP Raptor running around anywhere.

 

what about when an engine alone sits on a dyno, it puts out a certain HP.. But when it gets attached to a car and then dyno'd that HP decreases. Do you think the weight difference plays a part?

 

My boots and helmet weigh 10 lbs. If I ride without them, I gain 10 hp??? I lost a bunch of weight (me not the bike) a while back, and the difference WAS very noticeable!

The one place that weight is critical is ON THE WHEEL! Adding/removing weight from the wheel has more effect than doing it anywhere else! On a bicycle they say "adding an ounce on the wheel is like adding a pound to the frame".

 

Horse power to weight ratio is important.

40hp / 400 lbs = 0.1 hp/lb

40hp / 350 lbs = 0.114 hp/lb

Every pound lost equals 1 hp gain... LOL, man would I like to ride a 250lb Raptor then I would have a 195hp ATV!

 

Most say it is every 7-10lbs = 1hp.

 

who ever told you that is retarted!!, you wont gain hp by adding or removing weight!! horse power is only a measure of how fast you can do work, torque is how much work you can do. but if there is less weight your quad has less to overcome to make it move, so your power to weight ratio increases making it potentialy faster. as for an engine dyno, the only load on the engine is itself, once it is in the car power is measured through the clutch, transmission,drivetrain,rearend,and tires so the engine has the same power but you wont see all of it because it cost a certian amount of power to transmit it to the tires, thats why it is less.