Pirelli Wet Weather Tyre issues?

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Jackles-UK
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Pirelli Wet Weather Tyre issues?

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Having seen the last few races being thrown into utter chaos by the prevailing weather conditions it got me to thinking about the effectiveness of the Pirelli inter & wet tyres because at both races the cars seemed to be driving across sheet ice rather than damp or wet asphalt.

Of course I understand that with SEVERE amounts of water the cars just will not work but the first part of Q2 at Hockenheim today was no more really than a moderate showering of rain and the cars were totally at a loss for grip. I have to say that I don't really recall anywhere near as much terror in the Bridgestone days (although Korea '10 is the first exception to pop into my head, that really was a SEVERE amount of rain!).

Again there are many variables in a comparison between effectiveness of the two brands (rate of fall/surface/camber/temp etc) but Paul Henbury said on the BBC at Silverstone that the wet tyres displace 60l of water per second, intermediates around half that, does anyone remember the displacement figures for the old bridgestone tyres to compare?

Certainly a quick look at the difference in profile of the two manufacturers' offerings throw up a massive change in ethos. The Pirelli inters are like slicks with grooves cut into the face and their wets seem to have more surface area at the contact patch and less grooves to part the water, perhaps leading to more aquaplaning.

Anybody agree with me on this?

PhillipM
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Re: Pirelli Wet Weather Tyre issues?

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Bridgestone quoted a figure of about 60L/Second at 180+ mph.

Lycoming
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Re: Pirelli Wet Weather Tyre issues?

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It looked pretty wet out there, though its hard to judge on TV. Although I only saw alonso's pole lap, his grip seemed to be pretty ok under braking. Going wide isn't really an indication of struggling. With the heavily cambered corners of the hockenheimring, there's less standing water around the outside edge.

ESPImperium
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Re: Pirelli Wet Weather Tyre issues?

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Bridgestones wet weather tyres bere based on either their medium or soft tyres depending on the track.

Their extreme wets used to lift 80 litres a second at 250Kph, whitch is their theoretical maximum speed, however could do a bit more as Bridgestone usually always engineered a extra 20% of a marjin into their tyres. Pirellis wets can only do 60 litres a second at 280Kph, whitch is their limit pretty much.

As for the Inters, Bridgestone did 55 litres a second at 275Kph and Pirelli can only do 40 litres a second at the same 280kph.

Bridgestone also had alot of great things about their wet weather rubber, they did take a week at Nurburgring in 2005 with the Jordan team and a Ferrari test team to test their wet rubber in the middle of March of that year, it was the same mythical test it started snowing and they sent out 3 cars just to get data on snowy conditions.

Bridgestones wets were supperior to the Pirelli wets, but remember there was a Tyre war on then, and even tho Bridgestone had good wets, their wets were suppased by Michilens, but Bridgestone had much better inters then than the French company.

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Jackles-UK
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Re: Pirelli Wet Weather Tyre issues?

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@ESPImperium

Wow, I never realised that there was such a marked difference between the two suppliers! The Pirelli's being between 25% and 40% less effective is astounding!

The inter rate is not too much of a surprise if i'm honest, it just confirmed my thinking. I remember Button once using the Inters (whilst most others were on full wets) before the track dried and he took advantage of their softer nature and used them as set of slicks! They were a truly incredible and durable breed of tyre!

Maybe Pirelli do need to take a bit of time on their R&D for these two tyres (although understandably organising a tyre test in guaranteed rain is impossible!) as I know they didn't alter the compounds for this year as they did with the slicks (changed to different colour side-walls is all). Being completely different from previous suppliers is fine to a certain extent, but surely taking a leaf out of their experiences with what did and didn't work couldn't hurt?

Saribro
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Re: Pirelli Wet Weather Tyre issues?

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Jackles-UK wrote:organising a tyre test in guaranteed rain is impossible!
Paul Ricard HTTT has sprinkler systems.

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raymondu999
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Re: Pirelli Wet Weather Tyre issues?

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Saribro wrote:
Jackles-UK wrote:organising a tyre test in guaranteed rain is impossible!
Paul Ricard HTTT has sprinkler systems.
They did this in Yas Marina too:
Image

[youtube]http://www.youtube.com/watch?v=R6IdM99Dgh8[/youtube]
[youtube]http://www.youtube.com/watch?v=bzSx1YazwrM[/youtube]
[youtube]http://www.youtube.com/watch?v=TlgU9QSKxs4[/youtube]
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mx_tifoso
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Re: Pirelli Wet Weather Tyre issues?

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Yet I doubt it compares to a real world scenario where it's raining bucket loads at that very instant?
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ESPImperium
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Re: Pirelli Wet Weather Tyre issues?

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Jackles-UK wrote:@ESPImperium

Wow, I never realised that there was such a marked difference between the two suppliers! The Pirelli's being between 25% and 40% less effective is astounding!

The inter rate is not too much of a surprise if i'm honest, it just confirmed my thinking. I remember Button once using the Inters (whilst most others were on full wets) before the track dried and he took advantage of their softer nature and used them as set of slicks! They were a truly incredible and durable breed of tyre!

Maybe Pirelli do need to take a bit of time on their R&D for these two tyres (although understandably organising a tyre test in guaranteed rain is impossible!) as I know they didn't alter the compounds for this year as they did with the slicks (changed to different colour side-walls is all). Being completely different from previous suppliers is fine to a certain extent, but surely taking a leaf out of their experiences with what did and didn't work couldn't hurt?
That was Hungary 2006, Button switched 4 laps earlier, lost 4 places on the first out lap, then another 2 places on the next 2, then he switched them on and started to make those places back and whilst the rest were on the wets for another 2 laps, he managed to make it to second, then Alonso had his wheel issue, and then went on to win for Honda, their only win.

It was the only time that Michelin won with the Inters over the Bridgestone guys as they spent nearly €12.5m in R&D costs to get those tyres up to almost Bridgestone spec, but were still a tenth off in raw pace of the Bridgestone inters in the hands of Alonso or Kimi then. Just 1 week later they announced their pull out.

Developing wet weather tyres for F1 is costly, as you just have to wait arround for a wet track or go to a track that has a simulated wet track system like Paul Ricard, and hope there isnt a hosepipe ban, or the track has its own supply from a lake. I hear that Austin is to have this installed as they will have their own lake, and Pirelli are looking to use it once its installed after this years USA GP.

Pirelli are looking to develop their wet tyres, however they need to get a compound that is easy enough for most drivers and cars to switch on, however a compound that can last a massive distance. Wets should last up to 250-300Kms and Inters should last 185-215km, but arnt somehow.

Pirelli need to spend some time and money on their wet weather tyres as they just arnt good enough. The one way id go about it is spend late September and early October at Sliverstone as theres at least a 60% chance that you will get at least 2 days full wet weather running, and they need to get at least 2 GP2 cars and the R30 chassis out on track with developmental rubber on them.

I have noticed that in the past 3 or 4 years that you will have at least 20% or 30% of the 20 races on the callender wet. This year has had every weekend but two with at least 1 wet session so far, even race day in Bahrain had rain falling at the start, but it was so hot there that it evaporated instantly. Valencia was the last GP that wasnt weather affected. And the chance of a wet GP id rate at arround 25% every weekend, whitch means there will be arround 5 wet GPs a year.

This is good enough for me for there to be a push in development in wet tyres, the current slicks are good enough for me, maybes a little gardening needs done on the operating windows of them, but that is being done. I think Pirelli will now look at wet weather tyres next for a development push.

Pirelli have done a 8.5 out of 10 job for me, they arnt as good as the Bridgestones or Michilens yes, but have they done what was asked of them in their breif, i think so.

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Jackles-UK
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Re: Pirelli Wet Weather Tyre issues?

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mx_tifoso wrote:Yet I doubt it compares to a real world scenario where it's raining bucket loads at that very instant?
I agree, pouring water on Yas Marina is all well and good but when the air temp is ~40°C and track temp likely to be higher than that won't give the true simulation of a wet track on a wet day.

ESPImperium is right, they have improved the racing in the 80% of the season spent on slicks no end but slightly reduced the spectacle of the remaining 20% - still a big net gain!