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Old 23rd January 2006, 18:20   #16
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Firebird turbo Busa will whop the Veyron in a straight line. 0-60, top speed, you name it, turbo on turbo, bye-bye Veyron.
I know that, but look at the diff in power to weight between the 2 machines. It still doesn't prove, that a bike with the same power to weight ratio as that of a car (even if you consider the driver/rider) can match it.

Quote:
Yeah I know I went off topic but this was important, now coming to which ones wastes more power(I am excluding the driver/rider on this): I would say that bikes waste lesser power due to the design of the mechs and lesser moving parts as compared to anything on 4 wheels. ( % wise, I wouldnt even bother as they do not match up on an equal scale)
We're not just considering the power reaching the wheels. It's the % of power reaching the wheels which can be converted into acceleration.

A bike has less power, but less weight to carry too. Thats where power to weight comes in.

And about the 2 F1 car example. Yes i agree with you, that the car with the body shell and downforce will be quicker but, thats got everything to do with the design flaw on the other car.

The fact is, that F1 cars don't run that way. If they did, then i'd agree that cars waste more % of their power. Cars can be made to waste more power but, by default, they're not meant to do so.

U say power to weight is not important. Then how would you pit 2 equal machines? Based on their power output? (even thought the first car weighs twice the other one?).

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how about putting them on a drag strip? Why restrict the test to a circuit?
Then, how about giving them the same power to weight ratios (including the driver/rider). U wont bcoz you know the bike wont come anywhere close to the car bcoz, it's not able to that power to weight as well as the car.

PS: Guys, please don't take any of this personally. Lets look at it as a technical discussion and not as a way of discriminating machines.

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Last edited by Shan2nu : 23rd January 2006 at 18:42.
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Old 23rd January 2006, 18:35   #17
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Then, how about giving them the same power to weight ratios (including the driver/rider). U wont bcoz you know the bike wont come anywhere close to the car bcoz, it's not able to that power to weight as well as the car.
life is not fair shan. On one hand you put a car vs a bike on a track and compare the 2. then on the strip you ask for a handicap to the car? You cannot run races with only vehicles of the same P2W ratios. Thats what makes it interesting.

When drag races are run, do you ever see technical regulations stating that the P2W ratio has to be X? They will have a minimum weight mentioned, but if another vehicle weight more, bad luck!

And, as Jat mentioned, all the figures you've taken are of the bike without the rider. Add 70 kg to the 160 kg weight of the and you can figure out how the p2w drops.

Last edited by Domnic : 23rd January 2006 at 19:36.
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Old 24th January 2006, 15:49   #18
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Firebird turbo Busa will whop the Veyron in a straight line. 0-60, top speed, you name it, turbo on turbo, bye-bye Veyron.
You dont get the point. The bike would be having more power to weight ratio then the Veyon. Not only that but way more power to weight ratio.

The thing you are talking about is the TomaHawk.

The question is which waster more power and the answer can be in two respects.

Car - A Karizma is faster then a Santro from 0 - 100.

Bike - It has more power to weight but sometimes is not able to match a car with less power to weight.

Anybody seen 5th gear video Car vs Bike vs Boat. One Honda CBR 1000RR, Formula 1 BAR Honda and a Honda Boat. The Formula 1 car just smashed the bike ( which was ahead for few meters) before Button used full power and blew the bike.
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Old 24th January 2006, 16:25   #19
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Is this meaningful?

Q: should we close this thread? Shan? Rtech?
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Old 24th January 2006, 16:35   #20
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Is this meaningful?
Yeah dude, ofcourse it is. Not that we'l ever see a MotoGP bike race an F1 car for championship points but, i think it has been a good discussion.

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Old 24th January 2006, 16:51   #21
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Quote:
Originally Posted by BUSA
The thing you are talking about is the TomaHawk.
.
No. The Tomahawk has 4 wheels. According to me, it's a topless car. Please go look up Firebird and turbo Busa on google. Ghostrider may be a helpful keyword too.


The question is which waster more power and the answer can be in two respects.
Quote:
Originally Posted by BUSA
Car - A Karizma is faster then a Santro from 0 - 100.

Bike - It has more power to weight but sometimes is not able to match a car with less power to weight.
.
Santro is what, 63bhp? And 9.8 kgm. With a kerb weight of 854 kg. Let us add 10kg of fuel and a 70kg driver. We arrive at 854 + 10 + 70 = 934 kg.
PWR = 0.068 bhp/kg.
TWR = 0.010 kgm/kg.

Karizma is 150 kg. Add 80 kg to make it 230 kg. It produces 16.8 bhp and 1.86 kgm.
PWR = 0.073 bhp/kg.
TWR = 0.008 kgm/kg.

The bike therefore has only a 7% PW advantage, but a 25% TW disadvantage. Now, the bike is STILL faster to 100 kmph.

Please feel free to correct my calculations, if they are wrong.
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Old 24th January 2006, 16:56   #22
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You dont get the point. The bike would be having more power to weight ratio then the Veyon. Not only that but way more power to weight ratio.
Yup, the question is simple. Can a bike, acc as quickly as a car, with a similar power to weight ratio (even in a straight line).

And if it can't, then it isn't able to use that power to weight ratio as effectively as a car.

I agree with what Psycho said in his earlier post. From the engine to the wheels, the bike has less to lose since there are fewer moving parts.

But, the car gains it all back, when it comes to converting that power at the wheel, into acceleration.

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Old 24th January 2006, 17:02   #23
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But what are the acc figs of the Karizma and Santro? 0-100 i mean.

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Old 24th January 2006, 17:16   #24
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Santro 0 - 100 - 16.xx, Top Speed - 140

Karizma 0 - 100 - 14.xx Top Speed - 125
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Old 24th January 2006, 17:45   #25
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Obviously. Look at the shape of the Santro. In this case, it's the design flaw of the car, that makes it slower but, i'l give you another example.

Honda NHC - 1045kgs - 77bhp. Now add 80kilos (driver and fuel) to that.
1045 + 80 = 1125.
PTWR - 68.44 bhp/ton or 0.068 bhp/kg.
0-100 - 13.XX - Top Speed - 171.

With less power to weight, it performs better.

PS : U can neglect the top speed if you want, coz that is more dependent on the engine capacity than on ptwr.

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Last edited by Shan2nu : 24th January 2006 at 17:48.
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Old 24th January 2006, 18:03   #26
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Well. I wouldn't call the Karizma, with a rider atop, the epitome of aerodynamic perfection.

Maybe the NHC does this because it has the highest TWR of the three. Doesn't torque count for something?
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Old 24th January 2006, 18:20   #27
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Maybe the NHC does this because it has the highest TWR of the three. Doesn't torque count for something?
It helps more in roll ons from higher gears than during outright acceleration.

Hate to go off topic but you leave me no choice.

Yor car has a better ttwr than my car but, we all know which is quicker from standstill. And we also know that your car will be quicker in the roll ons.

If ttwr mattered that much, diesels would have been much quicker than what they are (without producing much bhp).

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Old 24th January 2006, 18:31   #28
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But the OHC has a better PWR than my car, and yet mine is faster. Now what?
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Old 24th January 2006, 18:40   #29
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But the OHC has a better PWR than my car, and yet mine is faster. Now what?
I doubt. Whats the 0-100 of the OHC 1.5? It's 11 something right?

PS : Lets not go too much, off topic. We'll meet this weekend n i'll tell you whats what.

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Last edited by Shan2nu : 24th January 2006 at 18:43.
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Old 24th January 2006, 18:41   #30
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Baleno is quicker in the quarter-mile run. I have owned and driven both.
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