Horsepower vs Weight

DEMMYM

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Not sure if this can even be figured out but here goes.

Recently had my Busa on the Dyno, Showed 156 Hp ( pretty much stock )

My Buddy had his ZX14 on the Dyno 171 HP

I weigh 170 lbs He weighs I would guess 270 lbs. Im curious as to what HP is lost to how many lbs a rider weighs. Meaning the 100 lb difference between our weights how many Does he loose to me for the extra weight.

Come on M.I.T. Grads figure this one out for me.

Mr Brown

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On a bike it's about 10 lbs = 1 hp. Not an MIT grad, but I did stay at a holiday inn express last night:rofl:

Big D

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Well, before anyone gets too worked up over those numbers, they really don't mean much unless you both had your bikes dyno'd the same day, on the same dyno, back to back... There are so many variables that can affect dyno numbers it isn't even funny.... That 171 sounds high to me, in the absence of major modage...

D

Mr Brown

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Well, before anyone gets too worked up over those numbers, they really don't mean much unless you both had your bikes dyno'd the same day, on the same dyno, back to back... There are so many variables that can affect dyno numbers it isn't even funny.... That 171 sounds high to me, in the absence of major modage...

D
You better ask somebody about them 14's! Equal mods the 14's make significantly more power than the Gen 1 Busa. Fact.

Vonderbach

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I'm fairly certain that it's relative to the overall weight of the vehicle. In other words, 100 lbs is a huge additional amount of weight on a 500lb bike, so 100 lbs could make a major difference. I don't know the math, but logically speaking, I would assume you might have a shot.

Mr Brown

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I'm fairly certain that it's relative to the overall weight of the vehicle. In other words, 100 lbs is a huge additional amount of weight on a 500lb bike, so 100 lbs could make a major difference. I don't know the math, but logically speaking, I would assume you might have a shot.
It's got nothing to do with the overall weight of the vehicle. All that matters is how much weight each pony has to carry. (Power to weight ratio) In other words, if you were to remove 100 lbs from a 500 lb bike, but said bike only had 15 hp, it's not gonna make much difference to performance. Now if that same bike had 150 hp, adding 10 hp by removing 100 lbs would be noticeable.

Commuta_Busa

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look at the torque numbers and calculate the rear wheel thrust so you can compare losses in lbs. There are so many other factors though. Traction is one of your limiting factors. Obviously off the line the extra pounds helps so that more traction can be produced. For acceleration rates the extra weight hurts once your past the point of limited traction.

In the real world each riders abilities can make or break who wins.

Vonderbach

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It's got nothing to do with the overall weight of the vehicle. All that matters is how much weight each pony has to carry. (Power to weight ratio) In other words, if you were to remove 100 lbs from a 500 lb bike, but said bike only had 15 hp, it's not gonna make much difference to performance. Now if that same bike had 150 hp, adding 10 hp by removing 100 lbs would be noticeable.

But if an engine is geared for a low weight vehicle, wouldn't that 100 lbs make a massive difference in performance?

Mr Brown

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But if an engine is geared for a low weight vehicle, wouldn't that 100 lbs make a massive difference in performance?
I see your point, and gearing an engine would make a difference, however a 15 horse motor pushing 400 lbs isn't gonna be massively faster than the same motor pushing 500. Would a riding mower be way faster if you lost 100 lbs? Faster certainly, but still slow.

Vonderbach

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I see your point, and gearing an engine would make a difference, however a 15 horse motor pushing 400 lbs isn't gonna be massively faster than the same motor pushing 500. Would a riding mower be way faster if you lost 100 lbs? Faster certainly, but still slow.

In conclusion, the ZX14 is a lawn mower. :rofl:

crackerhead25

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P/W engine power output being divided by vehicle curb weight this will give you power to weight ratio

AJAY

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2008 Kawi14 = 485 lbs
Rider = 270 lbs
Net = 755 lbs
Power = 171
power/mass ratio = 0.226 hp/lb

2007 Hayabusa = 487 lbs
Rider = 170 lbs
Power = 156 hp
Net = 657 lbs
power/mass ratio = 0.237 hp/lb

So technically you should have about a 5% advantage in power-to-weight, but the following needs to be considered:

2007 Hayabusa = 487 lbs
Rider = 170 lbs
Misty's spikes = 132 lbs
Net = 789 lbs
Power = 156 hp
power/mass ratio = 0.198 hp/lb

Sorry dude, you lose 14% on power-to-weight, but at least you win on style. :rofl:

DEMMYM

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Buuuuuuuut If I throw a couple spikes at him it should slow him down a bit. :whistle:

miserycaptain

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Faster, slower, no matter, they will all be looking at that beautiful Busa either way! We are just prettier.......................FACT! :laugh:
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