Close look at Vettel's Tire before the moment...

[n_anirudh]

If 18" wheels were used, would there have been such a large deflection in the sidewall?

[mertol]

Compression... The black is the lip of the rim, the red is the shoulder of the tire. Notice the difference. Then notice the fact that the lip of the rim is hanging out about 3 cm over the sidewall on the bottom while compressed and laterally stressed.

http://s1193.photobucket.com/user/johnc ... 5.jpg.html

Your bottom black line is not in the right place.

[Just_a_fan]

Perhaps Pirelli's guidelines are wrong, but I can't possibly see them owning up to that

Will Ferrari own up if they've run the tyre outside of the parameters Pirelli gave?

[TAG]

Compression... The black is the lip of the rim, the red is the shoulder of the tire. Notice the difference. Then notice the fact that the lip of the rim is hanging out about 3 cm over the sidewall on the bottom while compressed and laterally stressed.

http://s1193.photobucket.com/user/johnc ... 5.jpg.html

Your bottom black line is not in the right place.

I meant to illustrate the rim lip edge. So it's actually the top black line that's not in the right place, but yeah it's not scientific by any measure. Just trying to illustrate the compression as the bead of the tire extends below the rim lip.

[iotar__]

Thanks TAG, I get it now

Perhaps Eau Rouge on that lap was the last straw.

When Pirelli's grant was not accepted nearly 2 years ago, its their responsibility to ensure that tires last the whole race distance on any circuit (total laps -1), any weather.

Yes, but they are designed to work on a racing track with regular amount of using kerbs, driving straight through couple of them time after time (off-track) on an unusually long stint and on a high speed track can be a factor that contributed to a tyre failure but I don't expect Ferrari to own to that.

Let's stretch it to make a point, he drives even further off track cutting it like Maldonado let's say couple of times and it's the 40th lap on this tyre, do you blame tyre manufacturer if something happens? At which point can you say it's OK for a tyre to fail, leaving all the other variables unchanged: tyre wear, temperature, pressure - all the "no indication of a problem"?

[mertol]

It's never ok to suddenly blow a tire unless it is caused by some kind of contact with other car or a track wall. Curbs, grass, gravel and high speed corners are things you usually find on a track and the tires should be capable of running over them all day long.

[dans79]

But how may the tire not be pressurized adequately anymore?

Two things come to my mind:
a) a slow puncture, caused by whatever reason.
b) reduced tire performance due to less rubber on the carcass

according to Ferrari/Pirelli the data coming from the car showed no changes to tire pressure or temperature.

[bdr529]

Thanks TAG, I get it now

Perhaps Eau Rouge on that lap was the last straw.

When Pirelli's grant was not accepted nearly 2 years ago, its their responsibility to ensure that tires last the whole race distance on any circuit (total laps -1), any weather.

I'm under the assumption that when Pirelli entered F1 they were mandated to make a tire that couldn't last the whole race,
I don't remember them using, 1 less lap of total race distance as the goal for the tire performance

[mertol]

You know the tires can last less than the whole race without blowing up.

[bdr529]

That's just the case, I haven't seen anyone use 1 set of tires for the whole race, so I really can't say what would happen

[Nickel]

That's just the case, I haven't seen anyone use 1 set of tires for the whole race, so I really can't say what would happen

Longest stints on pirelli rubber I could drum up were Rosberg in sochi with 303km, and Di Resta in Canada 2013 with 266km.

[bdr529]

That's just the case, I haven't seen anyone use 1 set of tires for the whole race, so I really can't say what would happen

Longest stints on pirelli rubber I could drum up were Rosberg in sochi with 303km, and Di Resta in Canada 2013 with 266km.

I'm not saying that it's Ferrari's fault nor I'm I sticking the blame on Pirelli, I don't know what happened ?
That didn't seem like a lot of laps on that tire, so I was surprised to see it let go, just like everyone else at Ferrari was.
But for that same reason, I real can't rule out that he didn't damage the tire running of the tack some where.

[Nickel]

I'm not saying that it's Ferrari's fault nor I'm I sticking the blame on Pirelli, I don't know what happened ?
That didn't seem like a lot of laps on that tire, so I was surprised to see it let go, just like everyone else at Ferrari was.
But for that same reason, I real can't rule out that he didn't damage the tire running of the tack some where.

Agreed. Just thought I'd throw a data point in re: stint length precedents.

[bhall II]

They only dumped the lap limit, while the others (min air pressure, chamber etc.) were pushed through.

http://www.f1fanatic.co.uk/2013/07/05/f ... punctures/

I saw that, too. I read it as only applicable to the German GP, though...

The FIA has instructed team to obey limits on tyre pressure and camber angle throughout the German Grand Prix weekend.

Either way, that rule, or lack thereof, shouldn't be so difficult to ascertain. There's no reason for this kind of stuff to be so opaque.

[dans79]

some excellent info/quotes
http://www.crash.net/f1/news/222330/1/m ... mpaign=rss

Following that race Pirelli reverted to a kevlar belt and I believe has used this ever since with very few problems. Additionally the FIA took steps to mandate minimum tyre pressures, camber angles and banned tyre swapping. Ever since then this has been the case.

Following that race Pirelli reverted to a kevlar belt and I believe has used this ever since with very few problems. Additionally the FIA took steps to mandate minimum tyre pressures, camber angles and banned tyre swapping. Ever since then this has been the case.

Maurizio Arrivabene seems to agree with that and told the press that 'we have an engineer and all the teams have an engineer from Pirelli, so what do you think that engineer is doing. He's not there to eat chewing gum, he's there to check the tyres, to follow all the runs that you are doing and to give the data to the team. We had zero warning, I can show you the paper.'