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Old 07-04-2005, 10:59 PM   #31
Jay-G
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the simple fact is that the bike would not be possible to drive. You could not keep the front end down. IT would do 0-60 in like .8 seconds. THe R1 has 190HP - and it is ridculously fast. As is the y2k superbike- 320 HP- 400 lbs. This supposed bike is cranking out almost three times as much? bullshit. It would not be possible. The bike would be able to go like 350 with proper aero
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Old 07-04-2005, 11:52 PM   #32
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Quote:
Originally Posted by CarEXPERT
"If you have an engine that revs higher, you would probably have a gearbox to bring the speed down more."- what do you mean by this?
What this means is this: If you have an engine that typically runs between 2000-5000rpm, and another engine that runs between 5000-10000rpm, it would make sense that the higher revving one would have a gearbox that has shorter ratios. This is so the cars can travel at the same speeds, eventhough the engines are turning at different speeds.

Quote:
Originally Posted by CarEXPERT
When you say there is more torque at 1st than 6th AT THE WHEELS. What about at the crank, because isnt torque just how much force the piston is being pushed down and it doesnt matter how fast or slow it goes just how much force. At 6th gear, isnt the crank putting out the same torque at in 1st gear but they are diffrent at the wheels because of the gear ratios?
Correct.
Remember, "at the crank" is before the gearbox, so it doesn't matter whether you're in 1st, 6th or reverse.

Quote:
Originally Posted by CarEXPERT
So when people measure wheel horsepower on a dyno, what gear are they in for the reading cause the gear ratio fixes the torque at diffrent gears.
If you read all the other posts about torque vs power, you'll see that the reason everyone gets confused is because there is a formula that directly links the two.
Power = Torque x Speed.
So, at the wheels, there's more torque in 1st gear, but less speed. In a perfect world, it would be exactly the same in any gear.
For example (at an engine speed of 5000rpm):
1st gear: Wheel speed = 1000rpm Torque = 400Nm
6th gear: Wheel speed = 4000rpm Torque = 100Nm

You'll notice that in both cases, the power would be the same, because 1000x400 = 4000x100. You have to fiddle with the units a bit, but the proportion is still the same.
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Old 07-05-2005, 03:35 AM   #33
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About 2 weeks ago some guy from here was clocked doing over 200 on his bike near here (thought it was 300 but sounds alittle high). Pretty scary shit when your only on 2 wheels, your guarranteed(sp?) to die if you hit anything.
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Old 07-05-2005, 04:11 AM   #34
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Quote:
Originally Posted by car_crazy89
About 2 weeks ago some guy from here was clocked doing over 200 on his bike near here (thought it was 300 but sounds alittle high). Pretty scary shit when your only on 2 wheels, your guarranteed(sp?) to die if you hit anything.
You're pretty much guaranteed to die if you hit anything at 40mph.


Quote:
the simple fact is that the bike would not be possible to drive. You could not keep the front end down. IT would do 0-60 in like .8 seconds. THe R1 has 190HP - and it is ridculously fast. As is the y2k superbike- 320 HP- 400 lbs. This supposed bike is cranking out almost three times as much? bullshit. It would not be possible. The bike would be able to go like 350 with proper aero

They didn't make it to be practical, but it was probably a publicity stunt or something to prove that can be done. A 767 was converted into a 4 wheel car a while ago, although not practical, it's cool to know that it can be done.
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Old 07-06-2005, 08:03 PM   #35
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Quote:
Originally Posted by car_crazy89
About 2 weeks ago some guy from here was clocked doing over 200 on his bike near here (thought it was 300 but sounds alittle high). Pretty scary shit when your only on 2 wheels, your guarranteed(sp?) to die if you hit anything.


It was the owner of a bike turbocharging shop. Clocked by a chopper. Fastest speeding ticket.
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Old 07-07-2005, 04:45 AM   #36
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POwer is not equal to speed times torque. Hp is equal to torque x rpm divided by 5250. Thats why on all dyno charts the torque line and hp line cross each other at 5250 rpms. And most people dyno their cars in the gear that is closest to 1:1 in manual ls1 f-bodies this is fourth and in 350zs its fourth or fifth i cant remeber.
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Old 07-07-2005, 04:48 AM   #37
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Quote:
Originally Posted by boggledbetween
POwer is not equal to speed times torque. Hp is equal to torque x rpm divided by 5250. Thats why on all dyno charts the torque line and hp line cross each other at 5250 rpms. And most people dyno their cars in the gear that is closest to 1:1 in manual ls1 f-bodies this is fourth and in 350zs its fourth or fifth i cant remeber.

In the gearbox gear that is closest to 1:1. Keep that in mind, the final gear doesn't go into effect.
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Old 07-07-2005, 05:13 AM   #38
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Quote:
Originally Posted by boggledbetween
POwer is not equal to speed times torque. Hp is equal to torque x rpm divided by 5250. Thats why on all dyno charts the torque line and hp line cross each other at 5250 rpms. And most people dyno their cars in the gear that is closest to 1:1 in manual ls1 f-bodies this is fourth and in 350zs its fourth or fifth i cant remeber.
Sorry, I'm an Australian engineer.... I got taught in metric:
Power [W] = Speed [rad/s] x Torque [Nm].
The 5250 is just a constant that handles the unit conversions. And because it is CONSTANT, the direct proportionality is not affected. Therefore, you could rearrange the equation to say:
Power [hp] x 5250 = Torque [lb-ft] x Speed [rpm]
As you can see, the Torque x Speed is still there, meaning that the gear shouldn't matter (in a perfect world with ideal transmission).
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Old 07-07-2005, 05:21 AM   #39
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The Metric system is vastly superior to our stupid SAE unit of measurement. I can't wait 'til the world wakes the hell up and changes over.

And here's what I have to say about basically this entire thread.




Holy Schnikeys, it's not that tough of a concept.
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