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Assuming 215 lb/f of torque, geared for 238 mph top speed, this sucker provides 1350 lb. of thrust to push, say, 600 lb. in 1st gear (assumed 110 mph top) Other figures

Gear Thrust TopSpeed

1 1350 110

2 1100 136

3 925 161

4 800 187

5 700 212

6 625 238

Instant somersaults in the first 5 gears, just twitch the throttle a bit. Or lift your head at 150 in 3rd gear and increase the high drag a tad.



Is this scary, or what?
 

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Re. previous post. Yes, I know you can't apply 1350 lb. of thrust to a 600 lb. bike; it'll either flip or smoke its tires. It's the two to one excess of thrust in first gear that makes me wonder how you control all this. In my case, it's easy. I just don't buy one.
 

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Re: 351 is great... for dyno shootouts

It can smoke its tires in all six gears at any RPM above 1500. What fun....
 

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1) You're talking lbs/HP; I'm talking pounds thrust to pounds of weight. The Hayabusa with a 150# rider and full of gas would be about 625# or 1.8 lb/hp. Add the rider and fuel to your figures and see what comes up.

2) I didn't say it was impossible to manage, just difficult. At no point can the rider open the throttle all the way on the supercharged Hayabusa without flipping or burning.

3) I'm talking street. On the track, it's a blast!
 

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That sort of goes for the Hayabusa, too. I assumed it had to be heavier than the stock one in my calculations. Look at that awesome rear tire !

But moderate boost on a light bike aimed at optimizing to power curve sounds wonderful to me. It doesn't hurt emissions or fuel mileage much and could actually smooth out power delivery with careful design.
 

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Re: Physics 101 NOT

Power = torque * rpm * a constant that varies with the units of measurement. As you say, it's the rate of doing work (applying force) and can be expressed in units of either applied force per second or foot pounds of torque per second. Torque in foot pounds can be converted to force:

Force = OA gear ratio * torque / effective wheel radius (units being feet and pounds). The constant for conversion of torque in f-lb to SAE HP is .0001806

Because peak torque and peak power happen at different rpm, they can't be compared directly.

It is too apparent in dyno curves.
 

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Re: Motorcycle Land Speed Record kind of talk

What's that last sentence?

The other limits on speed are aerodynamic lift/stability and keeping the center of drag low enouqh to keep the front wheel on the ground. That and cojones of brass.

(tyres?, a brit!)
 
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