Formula One tyres play a significant role in the performance of a Formula One car. The tyres have undergone significant changes throughout the history of Formula One, with different manufacturers and specifications used in the sport.
Formula One tyres bear only a superficial resemblance to a normal road tyre. Whereas the latter has a useful life of up to 80,000 km, the tyres used in Formula One are built to last less than one race distance. The purpose of the tyre determines the compound of the rubber to be used. In , tyre changes were disallowed in Formula One, therefore the compounds were harder as the tyres had to last the full race distance (around 300 km). Tyre changes were re-instated in , following the dramatic and highly political 2005 United States Grand Prix.
In grooved tyres were introduced with three grooves in the front tyres and four grooves in the rear tyres.〔http://www.f1technical.net/articles/1〕 Between and , regulations required the tyres to feature a minimum of four grooves in them, with the intention of slowing the cars down (a slick tyre, with no indentations, is best in dry conditions). They can be no wider than 355 mm and 380 mm at the front and rear respectively and the maximum diameter is 660 mm (670 mm for wet tyre). Slick tyres were reintroduced at the beginning of , along with aerodynamic changes intended to shift the balance towards mechanical grip in an attempt to increase overtaking.
For , Bridgestone became the sole tyre supplier in Formula One with the withdrawal of Michelin, and introduced four compounds of tyre, two of which are made available at each race. The harder tyre is more durable but gives less grip, and the softer tyre gives more grip but is less durable. Both compounds have to be used by each car during a race and the softer tyre had a painted white stripe in the second groove to distinguish between compounds. This was introduced after the first race of the season when confusion occurred because a small dot was put on the sidewall of the tyre, instead of the white stripe. Upon the reintroduction of slicks in 2009, the sidewalls of the softer tyres were painted green to indicate the difference in compound, as there were no longer any grooves in tyres. Each team must use each specification during the race, unless wet or intermediate tyres are used during the race, in which case this rule no longer applies.
In extremely wet weather, such as that seen in the 2007 European Grand Prix, the F1 cars are unable to keep up with the safety car in deep standing water due to the risk of aquaplaning. In very wet races such as the 2011 Canadian Grand Prix, the tyres are unable to provide a safe race due to the amount of water, and so the race can be red flagged. The race is either then stopped permanently, or suspended for any period of time until the cars can race safely again.
On 2 November 2009, Bridgestone announced their withdrawal from Formula One at the end of the season.〔 〕 Michelin, Cooper Avon and Pirelli showed interest in taking over the role of tyre supplier. In June 2010, it was announced that Pirelli would be the sole tyre supplier for and would receive a three-year contract.〔(formula1.com confirming Pirelli for 2011 )〕 During August 2010, Pirelli commenced its test programme with the Toyota TF109 at the Mugello Circuit with Nick Heidfeld as the test driver.〔(Pirelli commence tyre testing )〕
With the sole tyre supplier having been changed from Bridgestone to Pirelli, the rules were the same as the 2010 season rules concerning the tyres. All teams still were required to use each type of dry tyre compound supplied in the race, and drivers that made it through to Q3 still had to use the same tyres they used to set their fastest qualifying time with to start the race. However, the way of denoting different tyre specifications was changed. Rather than a green stripe denoting a softer compound, for each tyre specification, the lettering on the tyre would have a specific color. The hard compound would have silver lettering, the medium compound would have white lettering, the soft tyres would have yellow lettering and the super-soft tyres would have red lettering. For the wet tyres, the intermediate tyres would have light blue lettering and the full wet tyres would have orange lettering.〔Pirelli tyres to have six different colours for 2011 Formula 1 season (). Retrieved 28 March 2011〕
At the 2011 Malaysian Grand Prix, Pirelli introduced a coloured band around the outside of the tyre on the softer of the two dry compounds. This was due to confusion during the first round of the season. This measure was said to be a stop gap, with a permanent solution due to be implemented at the first European race of the season. The coloured line featured at the Chinese Grand Prix too.〔Pirelli tweak ahead of Malaysia () 7 April 2011〕 From the Turkish Grand Prix, the permanent solution was implemented; the option compound had a new marking.〔http://www.planetf1.com/driver/3213/6889405/New-markings-for-Pirelli-s-tyres〕 The option tyre had two thick coloured lines between the Pirelli and P Zero logos of each tyre, which made it easier to see the colour of the marking when the tyre rotates. The prime tyre remained the same markings as previously, though later in the season had the sidewall updated with the new markings.
According to regulations, both compounds, prime (harder) and option (softer) compounds must be used in a dry race, failing which a driver will be disqualified. If a race is suspended without both tyres being used, a 30-second penalty will be imposed. This requirement is waived should drivers need to use wet weather tyres.〔http://www.fia.com/file/31071/download?token=xkk2udqj〕
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