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#238471 - 21/10/2004 02:45 Does this seem even remotely possible?
tanstaafl.
carpal tunnel

Registered: 08/07/1999
Posts: 5542
Loc: Ajijic, Mexico
Is this for real, or is it some clever fakery?

tanstaafl.
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#238472 - 21/10/2004 03:14 Re: Does this seem even remotely possible? [Re: tanstaafl.]
SE_Sport_Driver
carpal tunnel

Registered: 05/01/2001
Posts: 4903
Loc: Detroit, MI USA
Um... I don't think so. No matter how much power that scooter could have, it would never get the traction to do anything with it.

I do like the steam from the intake though!
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Brad B.

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#238473 - 21/10/2004 06:38 Re: Does this seem even remotely possible? [Re: tanstaafl.]
andym
carpal tunnel

Registered: 17/01/2002
Posts: 3995
Loc: Manchester UK
Isn't it obvious that the video is seriously sped up? What I want to know is what's stuff coming out of the car when it revs, N2O?
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Andy M

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#238474 - 21/10/2004 12:49 Re: Does this seem even remotely possible? [Re: SE_Sport_Driver]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
The Trans-Am clearly pulled ahead at the beginning. We never had a clear view of what happened afterward. The other part of the scooter that would make it impractical for max-acceleration burnouts is the high center of mass with a standing rider. How do you balance the thing? Weight forward to keep it from doing a wheelie? Weight backward to keep the drive wheel from spinning?

I imagine you'd have better luck if you put the same engine into some kind of kart. Then you've got two rear wheels, a lower center of mass, and maybe a fighting chance against the Trans-Am. I don't know the quarter-mile times on racing karts, but in anything involving turns and twisties, I imagine a kart would blow away a Trans-Am.

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#238475 - 21/10/2004 13:07 Re: Does this seem even remotely possible? [Re: DWallach]
SE_Sport_Driver
carpal tunnel

Registered: 05/01/2001
Posts: 4903
Loc: Detroit, MI USA
In turns and twisties, almost anything would be a TransAm! But yes, those karts FLY because of their power to weight ratios.
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Brad B.

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#238476 - 21/10/2004 17:42 Re: Does this seem even remotely possible? [Re: DWallach]
TigerJimmy
old hand

Registered: 15/02/2002
Posts: 1049
Not to pick nits, but motrocycles have a *lower* center of mass when standing, because your weight is taken by the pegs, rather than by the seat. This is a major reason why dirt riders and trials riders are often standing.

Jim

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#238477 - 21/10/2004 19:18 Re: Does this seem even remotely possible? [Re: TigerJimmy]
DzlDubber
stranger

Registered: 13/02/2002
Posts: 36
Well that flies in the face of conventional physics, i would think.

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#238478 - 21/10/2004 19:24 Re: Does this seem even remotely possible? [Re: DzlDubber]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31575
Loc: Seattle, WA
Yeah, interesting puzzle!

Sounds like a perfect CarTalk puzzler. Doug, send it in to them.

Oh, but don't you need to work out the answer first?
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Tony Fabris

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#238479 - 21/10/2004 19:26 Re: Does this seem even remotely possible? [Re: tfabris]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31575
Loc: Seattle, WA
I love Google. I really do.

http://www.msgroup.org/TIP142.html

I don't care if they take over the world. I, for one, welcome our new Google overlords.
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Tony Fabris

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#238480 - 21/10/2004 21:06 Re: Does this seem even remotely possible? [Re: andym]
lockuplever
enthusiast

Registered: 30/01/2002
Posts: 264
Loc: Tucson, AZ
What I want to know is what's stuff coming out of the car when it revs, N2O?

Yes, he is purging the system. This makes sure the nitrous is at the solenoid when he hits the button (or however he activates it) it also is a way to lower the bottle pressure, if it's too high.
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Steve

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#238481 - 21/10/2004 21:38 Re: Does this seem even remotely possible? [Re: lockuplever]
SE_Sport_Driver
carpal tunnel

Registered: 05/01/2001
Posts: 4903
Loc: Detroit, MI USA
I was thinking it was fake because the scooter made the same steam stuff.
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Brad B.

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#238482 - 22/10/2004 00:18 Re: Does this seem even remotely possible? [Re: SE_Sport_Driver]
PaulWay
addict

Registered: 03/08/1999
Posts: 451
Loc: Canberra, Australia
I thought that was just a gimmick, like an aerosol bottle taped to the steering upright to produce the same effect.

Let's put it this way, I'm sure the Trans Am could keep pace with the scooter, whatever speed or acceleration the latter did.

Noole,

Paul
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#238483 - 22/10/2004 06:59 Re: Does this seem even remotely possible? [Re: PaulWay]
tanstaafl.
carpal tunnel

Registered: 08/07/1999
Posts: 5542
Loc: Ajijic, Mexico
Let's put it this way, I'm sure the Trans Am could keep pace with the scooter, whatever speed or acceleration the latter did.


Upon what do you base this insight?

Acceleration is a function of power, weight, traction, and to some extent, wind resistance.

I'm guessing that the Trans-Am is probably kicking out about 500 HP, at a weight of 4000 lbs, for a weight to power ratio of 8:1.

The scooter + rider would weigh in at about 200 lbs (the guy looks pretty skinny) so if he were getting even 25 HP out of that thing, he'd match the Trans-Am. I'd not be surprised to find he had double that amount.

As for traction... you don't need a lot of traction to accommodate a GVW of just 200 pounds. We never get to see what sort of rear tire he has, but likely it is something along the nature of a 4" wide slick. You're probably looking at a contact patch of about 8 square inches. (4" x 2" x one tire)

If the Trans-Am were running 12" slicks, I'm guessing he'd have a contact patch of about 144 square inches (12" x 6" x two tires).

For the sake of the argument, figure comparable weight transfer to the rear for the Trans-Am and the scooter during acceleration.

The scooter will have very nearly the same wight/surface-area ratio as the Trans-Am. Relative tracton (as it pertains to developing acceleration) between the two should be similar.

I don't have a feel for evaluating the relative wind resistances of the two. Trans-Am has lots more frontal area, but man+scooter certainly could not be called streamlined.

Mechanically, I see no reason why a scooter race-prepped as this one was would be at a performance disadvantage.

Watching the video (it helps to watch it full-screen) it is apparent that the Trans-Am gets the better start. He is nearly half a second into the run before the scooter begins to move. By watching the two vehicles as they cross the light spots thrown down by the street lamps, it would appear that the scooter does indeed catch up to, and subsequently pass the Trans-Am.

Where this whole scenario becomes impossible in my mind is not the question of "is it mechanically possible", but instead the likelihood of being able to physically ride such an unstable vehicle at speeds approaching/exceeding 100 MPH. The very act of hanging onto the handlebars at that speed would induce frightening instability as the wind tried to blow the rider off the back of the machine.

I tend to agree with andym's assessment: the video is seriously speeded up. How far apart are those street lamps? In the first half of the run, they are covering the distance between them in about one and a quarter seconds. If the lamps were 250 feet apart (that seems reasonable) that means they would be traveling at 136 MPH, clearly not an attainable speed after less than 5 seconds of acceleration.

So, yeah, it's faked. But the reasons it has to be fake are not the reasons that most of you have suggested.

tanstaafl.
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