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JustWaitAFrekinMinute

On 6/11/2013 5:19 PM, JustWaitAFrekinMinute wrote:
On 6/11/2013 5:07 PM, wrote:
On Tuesday, June 11, 2013 3:23:55 PM UTC-4, iBoaterer wrote:
In article ,

says...

On Tuesday, June 11, 2013 8:54:07 AM UTC-4, iBoaterer wrote:

In article ,

says...

There must be some reason that nearly every track record is held by a

4 wheeled vehicle.

Cite?

Barcelona 2005

Formula One - Fisicella's Renault - 1:15.641 fast lap.

MotoGP - Gibernau's Honda - 1:42.337 fast lap.

PHILLIP ISLAND GRAND PRIX CIRCUIT LAP RECORDS

OUTRIGHT SIMON WILLS REYNARD 94D 13/02/2000 1.24.2215

FORMULA 4000 SIMON WILLS REYNARD 94D 13/02/2000 1.24.2215

PHILLIP ISLAND GRAND PRIX CIRCUIT

MOTORCYCLE LAP RECORDS

MotoGP Marco Melandri (Ita) Honda RC211V 1:30.332 16-Oct-05

Pole : Nicky Hayden (USA) Honda RC211V 1:29.020 16-Sep-06

A couple of results from a quick google. You can do the rest of the
work.

Pretty much the only tracks where you'll find faster times for bikes
are the tracks specifically designed for bikes. Cars obviously
enjoy enough of an advantage from their superior traction, brakes
and downforce that it negates the bike's advantage of less mass and
better power/weight ratio. Not by a lot, but 6 - 27 seconds (the
diff in the examples above) is a lot on a track.

Have fun.

Let's see. All tracks made exclusively with cars in mind.

Tracks that have taken special pains to cater to a bikes special needs
are faster for bike. Take that advantage away, and the car is faster.

Now, how about
REAL cites? How about the physics behind your ASSumptions? Superior

downforce??? You DO realize, don't you, that a motorcycle, when it leans

INTO the curve is keeping it's CG in line with the forces, while a car

isn't, correct?

You do realize that the CG of the bike, when leaning into a turn, is
attempting to push the tire ACROSS the pavement at the angle of the
lean? Meanwhile the car's down force is pushing the tire directly
down into the pavement. Keeping the downforce perpendicular is a good
thing.

Besides, the bike couldn't corner if it didn't lean to keep the CG in
line with the cornering force... that's what keeps it from flipping
over. That's also what causes the increase of slip angle and traction
loss.

On the street they lean inside in an attempt to keep the bike itself as
upright as it can be. They lean so far over the inside they often drag
their knee. In the dirt it's exactly opposite. we sit on top of the bike
in the corner leaning the bike onto the sidewall which also has grip...
This way we try to keep our weight downward as much as possible...
Here is a pic:

http://www.bing.com/images/search?q=motocross+corner+form&FORM=HDRSC2#view=de tail&id=C38AB0076CA6A392D9B898A37782E321807CB0AB&s electedIndex=29

Another little factoid.. The inside foot is not out to drag in MX, it's
thrown way forward to 1, keep it from dragging on the ground. 2 to put
that extra 15 pounds of foot, boot, and leg, up front to distribute more
rider weight forward toward the front axle...

Here is a better example of why that inside foot can't stay on the peg
and must go forward..:

http://www.bing.com/images/search?q=motocross+corner+positition&qs=n&form=QBI R&pq=motocross+corner+positition&sc=0-17&sp=-1&sk=#view=detail&id=99B32D5EC7AD33A7B347EE76BD6A5 815FECC62BD&selectedIndex=1

If he tried to leave it on the peg, he would leave it in the corner