The real reason for gathering marbles?

[ced381]

http://en.wikipedia.org/wiki/FISA%E2%80 ... led_Brakes

Interesting anecdote right there:

"During this period, the Formula One rules specified that any car must weigh at least 585 kg to be deemed in compliance with the rules. The method of testing was somewhat haphazard - teams would be notified that they would be "weight checked" when they exited the pits during practice or qualifying. This of course gave the teams ample opportunity to add weight to their cars while in the pits so as to pass the "test". Former Formula One driver Eddie Cheever offered an interesting anecdote from 1981 in which his Tyrrell was tagged for a weight check in qualifying. The team promptly took off the "racing" rear wing (a fiberglass/metal hybrid) and replaced it with the "weight check" rear wing before allowing him to proceed to the scale. Cheever said it took four of them to lift the "weight check" rear wing, and the car was largely undriveable with it installed. He believed that the weight check rear wing was made mostly of lead."

[Belatti]

I took off 0.5kg of marbles from a racing go kart. I believe that more than 1kg would be a good estimate in an F1 car, but maybe a little bit over the "new tyre" weight.

In the formula renault I work with the drivers are wighted after the podium. That explains why my drivers always spills the whole champagne bottle in their heads...

[MrBlacky]

I wonder, if you look at the first pic in this thread you can clearly see the outer side of the front tires are like new at all.

Everyone talks about maximizing the grip, but why then is 20% of the rubber unused?

[beelsebob]

I wonder, if you look at the first pic in this thread you can clearly see the outer side of the front tires are like new at all.

Everyone talks about maximizing the grip, but why then is 20% of the rubber unused?

Because running the cars with slight negative camber can provide some really nice handling characteristics. Basically, you're right when the cars are on a straight, 0 camber would be ideal. But in a corner, the car pushes over on the tyre. The outer, loaded tyre then flattens out onto the road and provides the largest contact patch just when you need it.

[Lurk]

But to dabble in the posts above:
You start the race with your car 640kg, driver no fuel EXACTLY..
You do the race, your driver loses 2kg, a piece of your FW gets hit off (.5kg?) and your tyre scrub down to the cliff (give me a figure of material loss here). You got your 2 litres of fuel in the tank (say 1.4kg).

Realistically, how much underweight could the car get? Any ideas?

Weighing after race is also done without any fuel so the 1.4kg of fuel must not be taking into account.

Teams always take some margin with the weight of their car because of the reasons you said. But even with that, you could end the race below the mandatory weight. For exemple if the driver have lost more weight than expected (3 to 5kg in Sepang), minor fluid leak, etc.
In case of involuntary bodywork damage, marshalls are allowed to make an exception if the car is below the mandatory weighing. But I think the team must prove that the underweighing is only due to the damages.

[Traction]

I wonder, if you look at the first pic in this thread you can clearly see the outer side of the front tires are like new at all.

Everyone talks about maximizing the grip, but why then is 20% of the rubber unused?

Because running the cars with slight negative camber can provide some really nice handling characteristics. Basically, you're right when the cars are on a straight, 0 camber would be ideal. But in a corner, the car pushes over on the tyre. The outer, loaded tyre then flattens out onto the road and provides the largest contact patch just when you need it.

A contributing factor to the uneven wearing of the tyres is the hot exhaust gases passing over the inside of the rear tyres hence generating excess heat on the inner part of the tyres..

[MrBlacky]

I wonder, if you look at the first pic in this thread you can clearly see the outer side of the front tires are like new at all.

Everyone talks about maximizing the grip, but why then is 20% of the rubber unused?

Because running the cars with slight negative camber can provide some really nice handling characteristics. Basically, you're right when the cars are on a straight, 0 camber would be ideal. But in a corner, the car pushes over on the tyre. The outer, loaded tyre then flattens out onto the road and provides the largest contact patch just when you need it.

If this is the case the outer site should be at least worn a little.

[beelsebob]

I wonder, if you look at the first pic in this thread you can clearly see the outer side of the front tires are like new at all.

Everyone talks about maximizing the grip, but why then is 20% of the rubber unused?

Because running the cars with slight negative camber can provide some really nice handling characteristics. Basically, you're right when the cars are on a straight, 0 camber would be ideal. But in a corner, the car pushes over on the tyre. The outer, loaded tyre then flattens out onto the road and provides the largest contact patch just when you need it.

If this is the case the outer site should be at least worn a little.

1) I'm sure it is a little worn
2) Not anywhere near as much as the inside – given that it's an anticlockwise track, you're likely looking at leaning on the outside of the right tyre maybe about 40% of the time, the outside of the left tyre 30% of the time, and on a reasonably straight area 30% of the time, so you're looking at that area of the tyre taking load about 30-40% of the time that the other areas are taking load.
3) Who says tyres wear at an even rate? More so, who says the appearance of a tyre at a certain wornness changes evenly? It could well be that a 30% worn down tyre looks to be in reasonably good condition, while a 60% or 80% worn tyre looks like it's absolutely wrecked.
4) If wear is connected to the temperature of the area of the tyre, heating it by dragging it across the track 100% of the time (like a section of the tyre close to the inside edge) might cause it to sustain a much higher temperature than an area of the tyre only being dragged across the track 30-40% of the time.

For all these reasons, you might expect to see a *significantly* non-linear progression across the tyre of apparent wear.

[MrBlacky]

1) I'm sure it is a little worn
2) Not anywhere near as much as the inside – given that it's an anticlockwise track, you're likely looking at leaning on the outside of the right tyre maybe about 40% of the time, the outside of the left tyre 30% of the time, and on a reasonably straight area 30% of the time, so you're looking at that area of the tyre taking load about 30-40% of the time that the other areas are taking load.
3) Who says tyres wear at an even rate? More so, who says the appearance of a tyre at a certain wornness changes evenly? It could well be that a 30% worn down tyre looks to be in reasonably good condition, while a 60% or 80% worn tyre looks like it's absolutely wrecked.
4) If wear is connected to the temperature of the area of the tyre, heating it by dragging it across the track 100% of the time (like a section of the tyre close to the inside edge) might cause it to sustain a much higher temperature than an area of the tyre only being dragged across the track 30-40% of the time.

For all these reasons, you might expect to see a *significantly* non-linear progression across the tyre of apparent wear.

Well, didn't want a discussion here, just a clarification. Thanks anyway.