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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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Motorcycle Land Speed Record for $100k

Not only that, I can clearly explain how, and even why I should drive it. It seems like some of you repliers have an understanding of the forces acting on a motorcycle at its top speed, especially the idea that aero drag equals motive power, and motive power is applied through a contact patch between tire and surface. That's good.

I was there when my pal Richard Noble's Thrust SSC vehicle broke the sound barrier. I have special knowledge therefrom that could translate into a very substantial boost to the record.

If any reader wants to play hot rod games out at El Mirage with Team Hammerhead, let me know.
 

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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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Re: turbo is not like 2 stroke

Vboost comes into play at around 6000rpms and takes you to 10000 in a blur. If you go into a corner at say 5500 and whack it in the middle, you're asking for a bit of a thrill. Now, if you're smart enough to downshift and get the rpm's up to say 6500 when you go in, your power delivery will be very smooth and you won't ever know there is a "boost". I had tended to spend most of my time way up in the power band so as to always be "boosting". After riding the MAx for the first year, I didn't really notice the boost anymore, I guess I just got used to it. Now, as I had said before, it's gone. If you know how your bike handles, you should have no problems in tight turns. However this will make the first few weeks a bit interesting...lol..
 

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Re: Motorcycle Land Speed Record kind of talk

On a wheel-powered vehicle, the issue is drag versus traction.

As others have pointed out, the force from drag increases dramatically as speeds increase.

As jackbird was pointing out, regardless of how much horsepower or torque you have, there comes a point at which your traction at the rear wheel is insufficient to overcome the force from drag (plus all the other forces keeping you from going faster).

The obvious solutions are to either increase your traction, or decrease your drag (or both). If jackbird has some other solution, I, for one, would be interested in hearing it.

This is not news to most people that are attempting speed records, especially at low-traction venues like Black Rock or Salt Lake. Take a look at what they've done to get some ideas for possible solutions. For additional traction tips, I'd look to dragracing and F1. For additional aerodynamic tips, I'd look to rockets, planes, and solar-powered race cars.
 

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Re: Physics 101, Fluids 101, and Thermo 101

Er, um, not to sound like an ass, but, horsepower and torque *are* mathematically related, and it *is* apparent on dyno charts.

I don't know the formula off the top of my head, but I'm sure someone will post it.

Didn't you ever notice that the horsepower and torque curves *always* cross at 5300 rpm, and that a bump or dip in one *always* results in a corresponding bump or dip in the other (albeit of different magnitude)?
 

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Yeah yeah, sure sure

I don't what you guys are getting all worked up about. It's just a show bike, a custom one-off, some guys at the factory having fun. Remember that wicked-looking Yamaha streetfighter built on the Roadstar engine? How about the recent Honda NAS or the older Zodia cruiser?

What I'm trying to say is that there is no way in hell that bike is ever going to make it to the dealership intact. You may see a vastly tamer version that is vaguely reminiscent of it, but there is simply no way that a big corporation is going to unleash a beast like that on the public. Not with so many lawyers around, anyway.
 

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Re: Motorcycle Land Speed Record for $100k

Yah, but the ThrustSSC vehicle wasn't wheel-powered (the motive power wasn't applied through the tires' contact patches).

It was a land-speed record, meaning only that the vehicle was touching the ground the whole time (more or less). Short of jet-bikes, what kind of carry-over information are you trying to allude to?
 

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That is of course, why they put throttles on motorcycles. The ability not to be limited by engine output, is something that I would like to expierience. It would be incredible to be able to use your right wrist to maintain the tire at the edge of its adhesion, regardless of location on the track, bike attitude, etc.
 

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Sort of like when I race in the rain, but with MUCH better mid-corner and braking grip.
 

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Re: Physics 101, Fluids 101, and Thermo 101

Horsepower equals torque times rpm divided by 5252.

hp = torque x rpm/5252
 

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Have you ever ridden a sportbike on a gravel road? It is incredible to have the rear wheel spin on command, but it is also impossible to relax and very easy to go down. I used to live on a gravel road and I do not miss it at all.
 

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yeah,like i said before, i want my twin-turbo GSX-R1000/YZF-R1/CBR9XXRR/ZX-9R/ZX10-R and whatever UJM turbocharged

maybe i'll use the Navy F-14 TOMCAT's arrester hook and wire to brake!!!

LOL and apply for a pilot license.
 

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Re: Yeah yeah, sure sure

Yeah, you're right about the machine not making it intact however, I'll take a regular 'busa powered machine (even a 'detuned' 'busa engined bike... imagine... even more torque than stock!!!) in a funky streetfighter frame.

C'mon Suzuk... you can do it!!! We need a vmax for the 21st century.
 

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Re: Turbo lag and spooling costs

Nothing is free, a turbo will impose exhaust restrictions that will cost some horsepower. It's not as easy to measure the cost in horsepower for spinning a turbo as it is for a supercharger but there is still a cost; in a well designed system the exhaust heat will help spool up the turbo but the exhaust heat is not nearly enough to lead to zero loss.

A more important point concerning a turbo is that there is ususally some lag between throttle application and turbo boost. Even if the system is well designed and the lag is minimal (which usually means minimal boost), lag is bad for cornering on the edge. I'd rather not have a turbo bike, I'd prefer mormally aspirated or supercharged for the predictable throttle response. YMMV.
 
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