All throughout a race weekend, the stratagem of using a wide array of tyres during practice, qualifying and the race is one of the most talked about subject. More than 30,000 tyres are used in a single season which is simply astonishing. By now, you would understand the importance of pit stops and before we get onto what happens in the race, I would like to explain the concept of tyres in F1.
Pirelli, an Italian tyre company, supplies the tyres to be used by all the teams participating. There are basically 5 types/ compounds of tyres- Ultrasoft, Supersoft, Soft, Medium and Hard- all these tyres to be used in dry track conditions. In addition to this, there are Intermediate and Wet tyres which are grooved and treaded, used in case of wet or extremely wet track respectively. Each tyre is demarcated with different colours to identify them easily- Purple for Ultrasoft, Red for Supersoft, Yellow for Soft, White for Medium, Orange for Hard, Green for Intermediates and Blue for Wet tyres. But why so many varieties of tyres you ask. Well, each tyre has two characteristics, degradation and speed; degradation is the amount of tyre wear, the softer the tyre the faster the degradation and faster will the car go. For instance, the ‘Ultrasoft’ tyre will give you more speed but will only last around 6 or 7 laps in a race which will have more than 50 laps while the ‘Soft’ tyre will be slower but will last more than 15 laps. So, the strategy used in the race in regards to the tyres make all the difference in a race. The tyre strategy is also handled according to the amount of fuel in the car. In the Qualifying session, the fuel is kept at a minimum so that the cars can extract every millisecond of performance in terms of lap time and believe me every millisecond is as precious as Gollum’s ring (technically Sauron’s but.. you get the idea). The teams in Q3 run the softest tyre predictably to gain the front-most position on the grid. As of now, there is no refuelling during the race so the car starts with more than 75 kg of fuel and so the tyres on which the race starts will have more wear owing to the fuel load. As the race progresses, the fuel load becomes lighter and the tyres last longer. Each race, Pirelli nominates 3 compound of tyres to be used in that race and so the teams have to stock up on those tyres only and the maximum a team can stock is 13 dry sets of tyres and of these 13 sets, two sets of tyres are chosen by Pirelli to be reserved for the race. Additionally, one set of the softest compound will be set aside for Q3 Qualifying session. Teams are free to choose what they like for their 10 remaining sets from the 3 chosen compounds.
Tyre wear also directly corresponds to handling grip. We often hear drivers complaining about the lack of grip in the corners and requesting for a pit stop. If there is no grip in the tyres, there are chances of the car going off at corners and also locking up the tyres. But what’s locking up? F1 cars don’t have anti-lock braking systems, therefore it is up to the driver to apply the maximum amount of braking force while ensuring that none of the wheels actually stop (lockup). A locked wheel/tyre cannot steer and it cannot apply as much braking force as a rotating one. It also damages the tire, creating a flat spot which, aside from the damage, can also cause dangerous vibrations on the car.