Pirelli F1 tyres at 362.1km/h top speed
Pirelli has shown the effect of the most extreme speed to be clocked during the 2014 season on its Formula One tyres. At the Italian Grand Prix in Monza, Red Bull driver Daniel Ricciardo reached 362.1km/h while slipstreaming on the main straight. At that speed, Ricciardo’s wheel was rotating around 2,800 times every minute, or just under 50 times every second.
Pirelli says that these extreme speeds have a profound effect on the tyres. At full speed, frequently achieved during a lap of Monza, a Formula One tyre is often subjected to a downforce load up to 1,000kg. Another important aspect is that the high speeds generate a huge centrifugal force on the tyre itself.
Because of these loads, the footprint of the tyre increases and the part of the tyre against the ground is subject to a lot of deformation (featured picture above). The structure of the tyre has to be incredibly strong and elastic to cope with this constant flexing.
At the same time, the upper section of the tyre (illustration 2) is subjected to a big centrifugal force, but despite this the shape of the tyre does not change much: stretching by one per cent. This is due to the low weight and extremely high stiffness of the materials Pirelli supplies to Formula One.
The F1 tyres are designed precisely with these extreme forces in mind: during laboratory testing, before they even see a race track, the tyres are exposed to higher loads and forces than they would normally experience, and accelerated to speeds of up to 450km/h. Not only that, but they are also fired into solid surfaces at speeds in excess of 250km/h: simulating the impacts with kerbs for which Monza is also famed.
Pirelli says that similar speeds can be put through its ultra high performance tyres to the road by the world’s top supercars: many use P Zero tyres as original equipment. The road-going products share more than a name with its F1 equivalent; they also contain much of the same technology and design processes.