18 wheelers

For irrefutable proof that Formula 1 places road relevance at the very heart of its future technical regulations, look no further than the big black roundels that adorn each corner of a grand prix car. Where for 30 years the aspect ratios of F1’s front and rear tyres had been unchanged at around 75 and 65 respectively, from next season the ratios will reduce dramatically to around half that, give or take a digit or two at each end.

The history of F1 tyre sizes and aspect ratios – the relationship between sidewall height and contact patch width expressed as a percentage – is as complex as it is convoluted. While road car tyres gradually grew in width and reduced in sidewall height, for political and economic reasons F1 doggedly stuck to the 13in wheel sizes originally introduced during the 1980s. Indeed, a case could be made that the F1 trucks that ferry cars and kit have more contemporary tyre ratios.

Rewind to 1985. With Goodyear enjoying an effective monopoly that ran through to 1996, sporadic competition rarely got a look in. The US tyre brand saw no reason to follow road car trends simply to beat itself. When Bridgestone entered F1 in 1997, the Japanese manufacturer suggested lower aspect ratios, only to be rebuffed after Goodyear, afraid of losing its competitive advantage, threatened to leave should the dimensions be changed.

When Goodyear did depart, two seasons later, Bridgestone, now by implication the sole supplier, applied the same arguments, reiterating them when Michelin announced its entry a year later.

Advantages… include more direct response to steering and braking input, greater control over spring rates… and increased brake disc