2015 Belgian Grand Prix - 21-23 August

[Henk]

But continue blaming vettel...its not like weve seen this concern before, or pirellis reaponse blaming curbs/outside influences. Wait yes we have! You just gotta turn off your bias and look at the data (i know...silly request).

It doesn't really matter whether we've seen these concerns before or not. It matters what actually happened.

Facts:
• The tires were not excessively worn to the point where they might fail under normal conditions
• Vettel was repeatedly running off the track at turn 4.

That leaves us with two reasonable explanations:
1. Vettel damaged his tires by running off the track.
2. The tire had a manufacturing issue.

Hopefully after further investigation we'll find out which of these it is.

The only reason we are talking about Vettel going off track is because he claimed he hadn't gone off track. That doesn't mean his right rear tire stayed within the white lines throughout the stint. He obviously means that he hasn't been in dirty off track areas. The curb at the top off eau rouge is probably the cleanest point of the curve since it's in the middle of the racing line. It might even strain the tyres less since you save a lot of lateral load.

It's also unlikely that the right rear would have suffered the most from of track running. The left rear is more off track at more points which are dirtier. The right rear does however take the most punishment because most of the various high speed corners are left.

Another notion elsewhere in the thread was that Ferarri was running extremely low tyre pressures. This was banned after the Silverstone troubles.

[Henk]

Accidentally posted the same thing twice. On another note: Do you think Verstappen should have given the place back to Nasr if he hadn't pitted? Is the move really gaining an advantage or is this just giving each other space?

[Moose]

But continue blaming vettel...its not like weve seen this concern before, or pirellis reaponse blaming curbs/outside influences. Wait yes we have! You just gotta turn off your bias and look at the data (i know...silly request).

It doesn't really matter whether we've seen these concerns before or not. It matters what actually happened.

Facts:
• The tires were not excessively worn to the point where they might fail under normal conditions
• Vettel was repeatedly running off the track at turn 4.

That leaves us with two reasonable explanations:
1. Vettel damaged his tires by running off the track.
2. The tire had a manufacturing issue.

Hopefully after further investigation we'll find out which of these it is.

Sorry but the picture above of Hamilton's McLaren with ties worn down to the canvas and still inflated (not the only example of Bridgestone tires durability Iirc) without blowing up proves that the Pirelli tires are simply not up to F1 quality levels and imo never have been.

As Webber used to say, they are Mickey mouse tires and shouldn't be in F1.

I disagree that it proves any point. As we've just covered - Vettel's tires were not worn down to the canvas (or in fact anywhere near). The failure was not caused by excess wear. The question then is, was it caused by damage, or production error.

2014: they went ultra conservative to the point that Rosberg did an entire race minus a lap on one set of tires.

I find it odd that you hold this against them, given that most people seem to say that Michelin were doing a great job - and this was exactly what they were doing - providing tires that were so durable that one set could last a race trivially.

[sgth0mas]

Continue ignoring the rest of the points against your argument moose...it adds credibility...

You do realize that pirelli themselves said it was because they were too worn right? They brought up the whole request for lap limits 2 years ago just to distract people like you so they dont look bad.

[Moose]

Continue ignoring the rest of the points against your argument moose...it adds credibility...

You do realize that pirelli themselves said it was because they were too worn right? They brought up the whole request for lap limits 2 years ago just to distract people like you so they dont look bad.

No, pirelli said that lap limits would have meant that this delimitation may not have happened. They did not say that wear was the cause.

We now have clear evidence that wear was not the cause - the other tires were not excessively worn.

There's no ignoring other posts going on here, just ignoring hysteria, and applying logic. If you have actual reasoning and not just "zomg, pirelli are awful" to use, please apply it.

[dans79]

2014: they went ultra conservative to the point that Rosberg did an entire race minus a lap on one set of tires.

I find it odd that you hold this against them, given that most people seem to say that Michelin were doing a great job - and this was exactly what they were doing - providing tires that were so durable that one set could last a race trivially.

Pirelli constantly brings up the fact, that they designed tires that degrade quickly because they where asked to. Russia showed they can't even do what the worked asked to do correctly.

Pirelli has been nothing but amateur hour from day one, they have dozens of people at every race, plus engineers embedded in the teams. Thus they should be well positioned to be very up front and dictate what the teams can and cannot do. They are never proactive though, they always seem to pray for the best and then react to any issues well after the fact.

They could easily have an issue with their tires just like they did in 2013. They had blistering problems in Malaysia, Hamilton's shredded left rear in Bahrain, and something else before Silverstone that i can't remember. They however didn't do anything until it became blatantly obvious to the world that something was wrong at Silverstone.

I don't want to even think what Indy 2005 would have been like if Perelli had been supplying tires at the time. They would have probably let them race, and then blamed the teams, drivers, or track for the issues after the fact.

[ringo]

The teams are hypocrites. They are in full support of Pirelli staying in F1.
Horner especially loves the mickey mouse races Pirellis give. He has no interest in michelin tyres, similarly with the other teams.
I can bet they change their tune now..

[ME4ME]

http://www.motorsport.com/f1/news/ferra ... re-failure

Sources have now revealed that Rosberg and Vettel were not the only drivers to face tyre problems at Spa-Francorchamps, with cuts being found in several other tyres over the weekend after practice sessions.

They must have removed that line of text because it´s not in the link you provided.

Nah, my bad. The first link should be to another Motorsport.com article. Fixed now.

[PlatinumZealot]

Also, zealot, you must not remember that pirelli switchef FROM steel TO aramid in 2013 because the steel exhibited wild delamination.

What technical basis do you even have to make comments on the aramid vs steel adhesion? Are you seriously just making this stuff up or repeating other people who have made this stuff up?

General materials knowledge. Certain materials bond to rubber better. Steel and brass are some. Kevlar is not that easy.

[PlatinumZealot]

I am not remembering any Bridgstone that has been down to the carcass, but it would be good is someone has any photos or videos so we can compare.

Here you go:-
http://img.vavel.com/Portada_Hamilton_187728221.jpg

Down to the canvas, still fully inflated.

A little peice of the carcass is showing not the entire thing like we saw with vettel. Thanks. Different construction it seems, The Pirelli peeled off from the outside edge like a banana. Like a whole layer of the tyre literrally got unglued from the carcass. The pirelli carcass is black and you could clearly see the fibres stretching and expanding as tyre rolled along. The bridgestone has a silver coloured carcass and it seems to be very strong bond that the layers seem to blend into each other. Not so for the pirelli. We see clear separations between the layers. Something as obvious as this not becsuse pirelli are amatuers at making tyres.... It is clearly because this is the construction that meets FIA demands.

Another video of the pirellie construction: you can see that the outer tread belt is vulnerable to being delaminated if it is breached.

[youtube]https://youtube.com/watch?v=sn3AcqpXe7c[/youtube]

[iotar__]

I see F1 tyres dissection based on tyre expert Vettel who had all the answers coming out the car and bad photos is still the main topic, I'll pass.

After re-watching:
- Coulthard is the worst - combination of local, Red Bull and overall bias. Grosjean had what 6-7 laps(?) newer tyres and was catching Vettel at the rate of 0,4-0,6 s most of the time and for him every understeer of a Ferrari (quicker and better on tyres car) was the result of huge tyre wear. As if it was 15+, overtake a formality, Lotus Mercedes on steroids and not slower car with 5 places penalty on a rather long stint too. Worse than Brundle - quite an achievement.

[sgth0mas]

It doesn't really matter whether we've seen these concerns before or not. It matters what actually happened.

Facts:
• The tires were not excessively worn to the point where they might fail under normal conditions
• Vettel was repeatedly running off the track at turn 4.

That leaves us with two reasonable explanations:
1. Vettel damaged his tires by running off the track.
2. The tire had a manufacturing issue.

Hopefully after further investigation we'll find out which of these it is.

Sorry but the picture above of Hamilton's McLaren with ties worn down to the canvas and still inflated (not the only example of Bridgestone tires durability Iirc) without blowing up proves that the Pirelli tires are simply not up to F1 quality levels and imo never have been.

As Webber used to say, they are Mickey mouse tires and shouldn't be in F1.

I disagree that it proves any point. As we've just covered - Vettel's tires were not worn down to the canvas (or in fact anywhere near). The failure was not caused by excess wear. The question then is, was it caused by damage, or production error.

2014: they went ultra conservative to the point that Rosberg did an entire race minus a lap on one set of tires.

I find it odd that you hold this against them, given that most people seem to say that Michelin were doing a great job - and this was exactly what they were doing - providing tires that were so durable that one set could last a race trivially.

http://www.motorsport.com/f1/news/pirel ... gp-weekend

"But although Vettel was seen running slightly wide across the kerb at Raidillon moments before his tyre failed, Pirelli is still convinced his failure was totally wear related.

When asked if there were any similarities between the two right rear tyre failures, Hembery said: "No. Rosberg was an external cut, this was pure wear.

"If you look at the images, the carcass was still intact so it was a wear issue, the second one on Friday was a cut." "

You have been wrong about evwrything you have said. You were wrong aboht the switch from steel to kevlar, wrong about the failures being just silverstone previously, and wrong about pirelli not claiming wear.

[CBeck113]

A little peice of the carcass is showing not the entire thing like we saw with vettel. Thanks. Different construction it seems, The Pirelli peeled off from the outside edge like a banana. Like a whole layer of the tyre literrally got unglued from the carcass. The pirelli carcass is black and you could clearly see the fibres stretching and expanding as tyre rolled along. The bridgestone has a silver coloured carcass and it seems to be very strong bond that the layers seem to blend into each other. Not so for the pirelli. We see clear separations between the layers. Something as obvious as this not becsuse pirelli are amatuers at making tyres.... It is clearly because this is the construction that meets FIA demands.

Another video of the pirellie construction: you can see that the outer tread belt is vulnerable to being delaminated if it is breached.

https://youtube.com/watch?v=sn3AcqpXe7c

And that statement is exactly the issue: the FiA gave Pirelli the goal to have the tires wear, they most certainly did not give them any design limitations or allow them to build tires which explode before they reach their design life limit and give the driver and/or teams no indication that the limit has been reached. THIS is the reason for the complaints against Pirelli, and they are justified. So justified, in fact, that I'm certain that the story will be changed to debris before Monza.
The picture from the Bridgestone tire worn down to its carcas shows that a tire can (and should!!!) hold its air even when its EOL has been reached, but his lap times went in the cellar for it.

@Moose: why do you think this isn't a design problem? The fact that it delaminated from the shoulder points more toward a design issue than a manufacturing problem.

[TAG]

I actually enjoyed the race, but this thread has become all about the tire discussion so trying to steer the technical discussion elsewhere. I had some observations which I posted some technical observations here;

http://www.f1technical.net/forum/viewto ... =6&t=23196 in the Chassis and Tire thread.

I believe there was quite a bit of abuse on that right rear of Vettel's car before the blow out.

[djos]

Finally finished watching the Race:

Fantastic race by the two RedBull boys and real shame Danny Ric had a total electrical failure as he was doing an amazing job up till then (2nd place on the podium was a real possibility). Danni Kyv really did a great job racing his way to 4th with some really nice clean moves, definitely earned some respect!

Great job by Roman G to get 3rd, really badly needed good result for Lotus and the driver formally doing a great imitation of "sideshow bob" (hair + crazy driving) seems to have finally matured and stopped making silly moves.

Seb really got hard done by with that tire fail, looking at the footage prior to the fail shows the tire was not looking ragged at all (no blistering etc) and I don't think Ferrari got this call wrong, his times were really stable and definitely not falling off the usual Pirelli cliff. I don't really like Seb much (too much prima donna eg Multi21) but he was the first driver to really master the rubbish Pirelli tires when the were 1st introduced, so 30 laps on them was well within his ability imo.