It's graining, men!

Everyone, to a greater or lesser degree, has been afflicted by the phenomenon that materialises under certain conditions and at various tracks that have specific characteristics and it can have a significant effect on tyre performance. But what exactly is graining?

We asked Pirelli Motorsport's Chief Engineer, Simone Berra, to explain. “Graining is a term used in motor racing to describe a phenomenon that occurs on the surface of the tyres,” he tells us. “When the surface of the tyre is subjected to stresses that reach a level where the compound starts to break up, microcracks form which lead to a surface irregularity on the tread, with peaks and troughs that vary in depth depending on the severity of the phenomenon. This graining then leads to a reduction in grip from the compound and has a significant effect on the car's performance when it is in mid-corner or under braking or acceleration. Graining occurs most commonly when track temperatures are low or when the tyres are not in the right operating window to provide grip. The circuit layout can also play its part, as can driving style and the way the car is set up. Managing graining is a vital part of strategy as it leads to tyre degradation and therefore affects the car's overall performance during a race.”

Got it? Well, tomorrow, before, during and after the race, there will be plenty more talk about graining. Whoever does the best job of managing it will undoubtedly get a good result while those who have struggled with it will complain even more than they have done so far.