RE: Pirelli's Silverstone fightback
Discussion
Inertiatic said:
Erm...read the press release again :-)
I have:Pirelli said:
Rear tyres that were mounted the wrong way round: in other words, the right hand tyre being placed where the left hand one should be and vice versa, on the cars that suffered failures. The tyres supplied this year have an asymmetric structure, which means that they are not designed to be interchangeable. The sidewalls are designed in such a way to deal with specific loads on the internal and external sides of the tyre. So swapping the tyres round has an effect on how they work in certain conditions. In particular, the external part is designed to cope with the very high loads that are generated while cornering at a circuit as demanding as Silverstone, with its rapid left-hand bends and some kerbs that are particularly aggressive.
This reads to me as the tyres being reversed on the rim. It initially looks like they're talking about teams swapping (correctly mounted tyres on) wheels from side to side on the car, but when it then goes on to talk about the "internal" and "external" sides of the tyre, it becomes clear that they're referring to tyres being mounted backwards, such that a left-hand tyre is mounted on a rim intended for the right-hand side of the car, ie. the inner sidewall ends up on the outer face of the rim.Weird wording, but I think that's what it means. Otherwise the wording about "internal" and "external" sides doesn't make sense, as swapping correctly mounted left wheels to the right of the car wouldn't change that.
jamespink said:
Donkey62 said:
woof said:
100% correct.
Pirelli fit all the tyres for the teams and each tyre is bar coded to a specific driver.
Although teams could request left tyre to be mounted on say right rim because Pirelli had absolutely no problems with doing that before Silverstone, for Pirelli to now say tyres are asyemetrical is total BS.Pirelli fit all the tyres for the teams and each tyre is bar coded to a specific driver.
The tyre pressures FIA should enforce absolute minimum tyre pressure some teams ran below 12psi at other circuits, a fart would have more pressure than that.
McSam said:
I have:
Weird wording, but I think that's what it means. Otherwise the wording about "internal" and "external" sides doesn't make sense, as swapping correctly mounted left wheels to the right of the car wouldn't change that.
that was how I read it first, but that can't be right as if you look at the pics, the markings are on the outsidePirelli said:
Rear tyres that were mounted the wrong way round: in other words, the right hand tyre being placed where the left hand one should be and vice versa, on the cars that suffered failures. The tyres supplied this year have an asymmetric structure, which means that they are not designed to be interchangeable. The sidewalls are designed in such a way to deal with specific loads on the internal and external sides of the tyre. So swapping the tyres round has an effect on how they work in certain conditions. In particular, the external part is designed to cope with the very high loads that are generated while cornering at a circuit as demanding as Silverstone, with its rapid left-hand bends and some kerbs that are particularly aggressive.
This reads to me as the tyres being reversed on the rim. It initially looks like they're talking about teams swapping (correctly mounted tyres on) wheels from side to side on the car, but when it then goes on to talk about the "internal" and "external" sides of the tyre, it becomes clear that they're referring to tyres being mounted backwards, such that a left-hand tyre is mounted on a rim intended for the right-hand side of the car, ie. the inner sidewall ends up on the outer face of the rim.Weird wording, but I think that's what it means. Otherwise the wording about "internal" and "external" sides doesn't make sense, as swapping correctly mounted left wheels to the right of the car wouldn't change that.
McSam said:
Inertiatic said:
Erm...read the press release again :-)
I have:Pirelli said:
Rear tyres that were mounted the wrong way round: in other words, the right hand tyre being placed where the left hand one should be and vice versa, on the cars that suffered failures. The tyres supplied this year have an asymmetric structure, which means that they are not designed to be interchangeable. The sidewalls are designed in such a way to deal with specific loads on the internal and external sides of the tyre. So swapping the tyres round has an effect on how they work in certain conditions. In particular, the external part is designed to cope with the very high loads that are generated while cornering at a circuit as demanding as Silverstone, with its rapid left-hand bends and some kerbs that are particularly aggressive.
This reads to me as the tyres being reversed on the rim. It initially looks like they're talking about teams swapping (correctly mounted tyres on) wheels from side to side on the car, but when it then goes on to talk about the "internal" and "external" sides of the tyre, it becomes clear that they're referring to tyres being mounted backwards, such that a left-hand tyre is mounted on a rim intended for the right-hand side of the car, ie. the inner sidewall ends up on the outer face of the rim.Weird wording, but I think that's what it means. Otherwise the wording about "internal" and "external" sides doesn't make sense, as swapping correctly mounted left wheels to the right of the car wouldn't change that.
Inertiatic said:
McSam said:
Inertiatic said:
Erm...read the press release again :-)
I have:Pirelli said:
Rear tyres that were mounted the wrong way round: in other words, the right hand tyre being placed where the left hand one should be and vice versa, on the cars that suffered failures. The tyres supplied this year have an asymmetric structure, which means that they are not designed to be interchangeable. The sidewalls are designed in such a way to deal with specific loads on the internal and external sides of the tyre. So swapping the tyres round has an effect on how they work in certain conditions. In particular, the external part is designed to cope with the very high loads that are generated while cornering at a circuit as demanding as Silverstone, with its rapid left-hand bends and some kerbs that are particularly aggressive.
This reads to me as the tyres being reversed on the rim. It initially looks like they're talking about teams swapping (correctly mounted tyres on) wheels from side to side on the car, but when it then goes on to talk about the "internal" and "external" sides of the tyre, it becomes clear that they're referring to tyres being mounted backwards, such that a left-hand tyre is mounted on a rim intended for the right-hand side of the car, ie. the inner sidewall ends up on the outer face of the rim.Weird wording, but I think that's what it means. Otherwise the wording about "internal" and "external" sides doesn't make sense, as swapping correctly mounted left wheels to the right of the car wouldn't change that.
Silverstone is a clockwise circuit.
Therefore most of the cornering will be round right handers.
Therefore there will be load on the left hand side of each tyre more than on the righthand side over each lap.
If you therefore need to reinforce a tyre to cope with this, you would reinforce the left hand side of the left rear (the outside) and the left hand side of the right rear (the inside).
If you then swap those tyres round, you have the strong bit where the weak bit should be and vice versa.
Is that not what they are saying?
Sorry to bring more doubt 
Scuffers, that photo is clearly a tyre correctly mounted but fitted to the opposite side of the car, yeah. That's not to say it's always the case, or the case in the catastrophic failures at Silverstone, though.
As for them designing the tyres to be handed for the circuit.. I thought this too, and there is a clear advantage, but I don't think the regulations would permit it. It would also have almost certainly been mentioned in all this furore, a rear left specifically designed to be a rear left at Silverstone not fit for its purpose, etc.. I think that, while the compounds and constructions might vary slightly from circuit to circuit, it's fairly safe to say there are no changes made between left and right to suit the circuit direction.
Scuffers, that photo is clearly a tyre correctly mounted but fitted to the opposite side of the car, yeah. That's not to say it's always the case, or the case in the catastrophic failures at Silverstone, though.
As for them designing the tyres to be handed for the circuit.. I thought this too, and there is a clear advantage, but I don't think the regulations would permit it. It would also have almost certainly been mentioned in all this furore, a rear left specifically designed to be a rear left at Silverstone not fit for its purpose, etc.. I think that, while the compounds and constructions might vary slightly from circuit to circuit, it's fairly safe to say there are no changes made between left and right to suit the circuit direction.
PascalBuyens said:
Not really.
Asymmetrical tyres are made to be used in one rotational sense, meaning they are designed to go forward fastest. Turn the wheel around and you're using the tyre as if you'd be driving your car flat out in reverse all the time. Which those tyres aren't designed for.
Not correct.Asymmetrical tyres are made to be used in one rotational sense, meaning they are designed to go forward fastest. Turn the wheel around and you're using the tyre as if you'd be driving your car flat out in reverse all the time. Which those tyres aren't designed for.
Edited by PascalBuyens on Wednesday 3rd July 12:36
Asymmetrical tyres only mean that there is a designated outside/inside. They can be run in either direction, therefore they can be swapped side to side without remounting.
Directional tyres can only be run in one direction (obviously) so if they were the same size they could be swapped front to rear, or flipped over and remounted so that they can be swapped to the other side.
Tyres that are BOTH asymmetrical AND directional can never be flipped during mounting and therefore can only ever be used on one side of the car, and if different sizes front and back, then only in one position on the car.
What DB9Volante said.
But with Pirelli's wording being a bit vague, we're not quite sure whether they're using "asymmetrical" to mean "directional" or not.. I still lean towards their point being that tyres were mounted backwards on rims, though, rather than wheels being swapped around the car.
But with Pirelli's wording being a bit vague, we're not quite sure whether they're using "asymmetrical" to mean "directional" or not.. I still lean towards their point being that tyres were mounted backwards on rims, though, rather than wheels being swapped around the car.
McSam said:
What DB9Volante said.
But with Pirelli's wording being a bit vague, we're not quite sure whether they're using "asymmetrical" to mean "directional" or not.. I still lean towards their point being that tyres were mounted backwards on rims, though, rather than wheels being swapped around the car.
In which case, Pirelli are still responsible because they put them on the wheels!But with Pirelli's wording being a bit vague, we're not quite sure whether they're using "asymmetrical" to mean "directional" or not.. I still lean towards their point being that tyres were mounted backwards on rims, though, rather than wheels being swapped around the car.
Scuffers said:
not really no.
Pirelli have always made some marginal tyres, that asides, they were the only ones that would make tyres to FIA performance spec's (as in wear out real fast)
so, ultimately, you have to blame the FIA not only for the spec of the tyres, but also they total inability to manage the situation, Pirelli to their credit saw this problem coming and tried to do the right thing, the FIA should have understood that, and told Red-Bull & Ferrari to STFU as opposed to the farce of tyregate, the results of which are where we are now.
OK then...Pirelli have always made some marginal tyres, that asides, they were the only ones that would make tyres to FIA performance spec's (as in wear out real fast)
so, ultimately, you have to blame the FIA not only for the spec of the tyres, but also they total inability to manage the situation, Pirelli to their credit saw this problem coming and tried to do the right thing, the FIA should have understood that, and told Red-Bull & Ferrari to STFU as opposed to the farce of tyregate, the results of which are where we are now.
Pirelli = right
FIA = wrong
F1 teams = to blame as they put the tyres the wrong way round... LOL!
marshalla said:
In which case, Pirelli are still responsible because they put them on the wheels!
I've always thought this - note that they mention in their press release "Mounting the tyres the wrong way round is a practice that was nonetheless underestimated by everybody: above all Pirelli, which did not forbid this.". That says to me they are accepting that they should always have forbidden buggering around with the asymmetry.
Pirelli are the innocents in all of this! The F1 teams needed to vote unanimously to change back to Kevlar construction and Lotus and Force India voted no! The FIA in the guise of Jean Dodo have been asleep at the wheel as I said previously. Drivers are on the kerbs, off the circuit into rougher run off areas and there is one corner at Silverstone where there seems to be a distinct step in the concrete and is covered in tyre rubber. The trouble with the current situation is "the show" was perceived as getting boring with Red Bull running away so changing the tyres to have less reliability was a deliberate step that F1 took and the teams supported that. Now the tyres failure can't possibly be their fault, running marginal pressures, aggressive cambers, and swapping tyres to the opposite sides of the axle to try and generate another advantage as some teams believed this lessened graining, but all outside of the manufacturers recommendations-so Pirelli are NOT to blame. The teams as usual are not saying a lot because they know what they have been doing is risky and it's the drivers who are having to take the risks ..with their lives. As usual it will probably be Bernie who bangs heads together and sorts it. Thank God he hasn't retired yet.
DB9VolanteDriver said:
Tyres that are BOTH asymmetrical AND directional can never be flipped during mounting and therefore can only ever be used on one side of the car, and if different sizes front and back, then only in one position on the car.
I suspect this is the case, the tyres are effectively asymmetric and directional. For clarification, as I understand it, say its the sidewall strength which is the part which makes the tyres asymmetric/directional, then you could have something like this from left to right:
strong weak | strong weak
so if you switch them round you get
weak strong | weak strong
which is obviously bad....
Agent Orange said:
GreigM said:
then you could have something like this from left to right:
strong weak | strong weak
so if you switch them round you get
weak strong | weak strong
which is obviously bad....
That's how I read the press release.strong weak | strong weak
so if you switch them round you get
weak strong | weak strong
which is obviously bad....
The way i read it is, Pirelli mount the tyres to the wheels and the teams simply swapped wheels side for side so the outside was still the outside just the tyre ran in the opposit direction, if the tyres had been swapped from wheel to wheel the arrow would point in the correct direction but the inner and outer walls would be incorrect, the pictures back this up with the arrow pointing in the wronge direction.
As i said on another thread i put this 60% the teams fault (taking the pee as F1 teams do)
40% Pirelli for not having enough control over making the teams stick to the recomended setting and or not realising the issue was a problem, you could argue they can't enforce the recomendations it's up to the FIA, in which case i see as still thier fault for not gaining that control from the FIA, it's in thier interests to stop the team making thier product look bad.
As i said on another thread i put this 60% the teams fault (taking the pee as F1 teams do)
40% Pirelli for not having enough control over making the teams stick to the recomended setting and or not realising the issue was a problem, you could argue they can't enforce the recomendations it's up to the FIA, in which case i see as still thier fault for not gaining that control from the FIA, it's in thier interests to stop the team making thier product look bad.
The teams have a tyre engineer assigned to them by Pirreli, they knew exactly what the teams were doing and co-operated with them in mounting the tyres backwards, they also gained data and gave feedback from all the tyre running that occurs on track. That is the role of the tyre technician. If there was any doubt about the cambers and pressures and mounting techniques, Pirreli knew they were risking the tyre safety and should have stopped what they were doing.
It shouldn't take a series of failures to prompt a tightening of the running conditions, they knew they were marginal and should not have allowed it to happen. It's a ridiculous situation to allow the teams to run a safety critical product so close to failure and in conditions that they knew were not designed for.
With regards to mounting techniques, having race tyres directional and load specific is nothing new. Take a look at something like an Avon slick, you mount the tyre based on the load path, on a RWD car like an F1 car you run the front and rear tyres in the opposite direction to each other, on a FWD you do the same, but with the tyres reversed compared to a RWD, on a 4WD you run them the same direction front/rear.
X is the tyre batch number embossed on the sidewall to use as reference.
RWD
FWD
AWD
It shouldn't take a series of failures to prompt a tightening of the running conditions, they knew they were marginal and should not have allowed it to happen. It's a ridiculous situation to allow the teams to run a safety critical product so close to failure and in conditions that they knew were not designed for.
With regards to mounting techniques, having race tyres directional and load specific is nothing new. Take a look at something like an Avon slick, you mount the tyre based on the load path, on a RWD car like an F1 car you run the front and rear tyres in the opposite direction to each other, on a FWD you do the same, but with the tyres reversed compared to a RWD, on a 4WD you run them the same direction front/rear.
X is the tyre batch number embossed on the sidewall to use as reference.
RWD
FWD
AWD
I expected all this after hearing the teams telling the drivers they were increasing the tyre pressures during the race "as a precaution" and then listening to Ross Brawn's guarded response to Hamilton's stroppy out-burst.
IIRC, the last time there was a GP at Spa there was a problem with teams (Red Bull in particular) running the tyres at a camber outside the recommended limit and Pirelli had to defend themselves.
Pirelli are stuck between a rock and a hard place.
IIRC, the last time there was a GP at Spa there was a problem with teams (Red Bull in particular) running the tyres at a camber outside the recommended limit and Pirelli had to defend themselves.
Pirelli are stuck between a rock and a hard place.
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