Thoughts on 2012 tyres?

[xpensive]

I'm not entirely convinced of the fuel-load being the culprit either, I have always, ignorantly perhaps, believed that the decisive parameter on the tyre is shear-force on the contact patch, which should not vary that much with the fuel-load at all?

[myurr]

Not sure I agree with the fuel load being the smoking gun. How does that amount of load compare to how much downforce the car generates? How does that variation in load with burnoff compare to how many thousands of pounds more or less downforce you have in a high speed or low speed corner?

F1 tires have always had the requirement of working through a wide load range by virtue of aero alone.

The load on the tyre isn't just the vertical component as produced by downforce though. You know far more about tyres than me but if the horizontal load is changing during the course of the race by a significant percentage wouldn't this affect the amount of heat generated in the tyre as well as the shear forces at the contact patch?

I'm not suggesting it's a smoking gun, merely pointing out that it is probably playing a part in individual drivers overheating their tyres in the opening stint.

Overall though I don't see why so many people are complaining about the racing. The field has never been so close and unlike 15 years ago we no longer have Sunday morning practice sessions, so being slightly out in terms of optimal setup will have a big effect given the competitiveness of the field.

[myurr]

I'm not entirely convinced of the fuel-load being the culprit either, I have always, ignorantly perhaps, believed that the decisive parameter on the tyre is shear-force on the contact patch, which should not vary that much with the fuel-load at all?

Then why do the tyres only last half as long, or less, in the opening stint when compared to the final stint?

[Jersey Tom]

The load on the tyre isn't just the vertical component as produced by downforce though. You know far more about tyres than me but if the horizontal load is changing during the course of the race by a significant percentage wouldn't this affect the amount of heat generated in the tyre as well as the shear forces at the contact patch?

The amount of in-plane force the tire can generate is directly proportional to the vertical force, sure.

Then why do the tyres only last half as long, or less, in the opening stint when compared to the final stint?

If that is indeed the case I'd attribute it to the track taking some rubber.

[xpensive]

Probably because the Pirellis are marginal in that respect, let's try a simple analysis;

- Lateral Force; F = mass * speed^2 / corner radius. Radius is a constant so forget about it.

- For the sake of argument, let's assume that maximum F is proportional to vertical load as F = N *mu.

- Suppose vertical load on one tyre with a full load of fuel is 200kg of mass plus aero load, say 5000 N.

- 120 liters and 100 kg later, if evenly distributed over four wheels, vertical load will be some 4750 N, only 5% less.

- As a consequence, max lateral Force F will also go down with 5%, while mass have decreased with 12.5%,
speed can increase to compensate as follows, see first formula;

Speed 2 = Speed 1 *(0.95/0.875)^0.5, which gives; Speed 2 = 1.042 * Speed 1.

A 4.2% speed increase might not seem much, but at 200 km/h it actually is.

[Paul]

Also, a heavier car, while generating similar lateral force at the contact patch, will generate it for longer period of time at each corner (because of lower cornering speed), thus working the tyre harder. At least that is how I see it.

[xpensive]

Also, a heavier car, while generating similar lateral force at the contact patch, will generate it for longer period of time at each corner (because of lower cornering speed), thus working the tyre harder. At least that is how I see it.

True, why you can say the same for braking and acceleration of course.

[elf341]

(And could you please let the F2012 know that it's supposed get better as it gets lighter? For some reason, it never got the message.)
F1 is weird.

+1

I also noticed the McLaren in clean air was between 2 to 3 seconds a lap slower at the end of the race than the Lotus.

[myurr]

(And could you please let the F2012 know that it's supposed get better as it gets lighter? For some reason, it never got the message.)
F1 is weird.

+1

I also noticed the McLaren in clean air was between 2 to 3 seconds a lap slower at the end of the race than the Lotus.

Hmmm I wonder if that has anything to do with having run 13-15 laps further on their tyres by that point in the race. Lewis had to make the tyres last twice the distance that the Lotus cars went on their last stint.

[jason.parker.86]

Hello,

I have had a random, but interesting thought on the Pirelli tyres this season.

Reading an article on ESPN F1 (http://en.espnf1.com/mclaren/motorsport ... 78955.html), I am wondering...

Could Pirelli deliberately be making some tyres last longer than others, and/or some tyres better than others? These "better" tyres could just be randomly placed into the batch and it's a complete lottery who gets them.

I am not saying it's a "fix"... but could this be Bernie's way of making F1 more interesting?

[AnthonyG]

[bhallg2k]

Join us here ( viewtopic.php?f=6&t=12601&start=300 ) where you'll find classics such as:

With Lotus' performance and a Williams winning the race, I'm not so sure it's luck either.

I wonder what effect F1's newfound parity is going to have on their planned IPO this summer.

The upcoming IPO is another angle to it of course, what's more xiting to the market than close racing, however artificial? Other than Williams and Lotus getting special treatment, I also suspect Sauber and perhaps even Alonso...oooops!

But why would this work especially well for Kimi and Grosjean and Maldonato and Alonso and not for Massa and not for Button?

The underlying logic is not really there ,at least to me when performance seems NOT to depend on how the driver uses the tyre and at the same time it is of paramount importance.

[...]

In each and every race now one or two teams have found the sweet spot in the race and funny every time it was a different one....That´s not matching with experience and knowledge gained....you would expect as time goes on more and more people finding the area where you need to be and the teams eeking closer and closer to the optimum.

My guess:without getting to know HOW teams get hold of their tyre allocation for the weekend you wonder how performance can be shifted through the field randomly
-when will Timo Glock have his lucky day and win the first time?

If you want conspiracy, we've got you covered, because, just like this year's Pirellotteri tires, we've lost our grip on reality, too.

[Nando]

Could Pirelli deliberately be making some tyres last longer than others, and/or some tyres better than others? These "better" tyres could just be randomly placed into the batch and it's a complete lottery who gets them.

What are the chances Maldonado picked the right tires in pretty much every single session?

[Speedster]

It's not that I don't think fuel load is a factor; obviously, it is. I should have said that I think Raikkonen's view is probably not representative of F1 drivers in general. Most have had 2+ seasons to figure it out, whereas Raikkonen is approaching only his sixth race.

(And could you please let the F2012 know that it's supposed get better as it gets lighter? For some reason, it never got the message.)

F1 is weird.

That's precisely the point Kimi is making, but in reverse. The F2012 seems to be working fine when it is heavy, both on tyres and on speed. It is when it is out of his optimal range (for the F2012 when it gets lighter for some reason) that it starts to struggle both tyre and speed wise. It's also interesting to see Kimi saying this, as he's in a car that is believed to be quite consistent and in a team where they seem to have the best understanding of the tyre and the effects of setup on tyres. This comment could also indicate that it's just the other teams not being smart enough yet to figure out what's going on. Maybe in 3 races tyres will be much less talked-about.

I'm still ambiguous myself. I have to admit I dropped out last season, because of the clear domination of one car. In that respect, this season is a lot better, with action (not necessarily overtaking) near the front. On the other hand, I remain duly unimpressed about the spike in overtaking recently. All those DRS overtakes that are marked by commentators as special (I'm looking at you DC with your comments on Vettels overtake on Hamilton last race), I cannot take them seriously. That's, as I've said earlier in this thread, not overtaking, that's driving past each other. On the other hand, we have seen some real overtaking, not necessarily in a superior car (Kobayashi comes to mind).

I also think that there is a lot of focus on the tyres, as the other parts of the cars are so similar. The gaps in qualifying are very small this year, indicating that the cars are close to each other in terms of speed. This means the attention switches to things that do make a difference. In 2011 it was the blown diffuser that was the bad guy, this year it are the tyres. I'm sure that if we got tyres that are more durable, there would be something else that is getting most of the attention.

[Speedster]

Could Pirelli deliberately be making some tyres last longer than others, and/or some tyres better than others? These "better" tyres could just be randomly placed into the batch and it's a complete lottery who gets them.

What are the chances Maldonado picked the right tires in pretty much every single session?

Good question. Are tyres allocated per driver or per team? And how do the teams split them up during a weekend?

I'm usually very reluctant to believe in conspiracies, and the big gap and more importantly, the consistency of that big gap during the weekend, between Senna and Maldonado lead me to believe this is nothing more than that: a conspiracy theory.