Why Paul Ricard's resurfacing is leading to the F1 car kerb-clattering


F1 teams have been complaining to Michael Masi about Paul Ricard's harsh kerbs – but as circuit designer Jarno Zaffelli explains, it's the drivers that have become more aggressive, not the track furniture

22 TSUNODA Yuki (jap), Scuderia AlphaTauri Honda AT02, action, during the Formula 1 Emirates Grand Prix de France 2021, 7th round of the 2021 FIA Formula One World Championship from June 18 to 20, 2021 on the Circuit Paul Ricard, in Le Castellet, France - Photo Marc de Mattia / DPPI

Paul Ricard is set to bring up track limits issue once more

Marc de Mattia / DPPI

F1 cars have been battering and bouncing their way across the bevelled kerbs at Paul Ricard this weekend, leaving trails of carbon fibre in their wake and infuriating teams faced with the repair bills from the “aggressive” rumble strips.

Valtteri Bottas damaged his front wing when he went wide onto kerbs in the Turn Two/Three section during free practice, with Max Verstappen doing the same in FP2.

Mercedes‘ team manager Ron Meadows let his (unappreciative) feelings be known to Race Director Michael Masi early on.”Those yellow rumble strips on the exit of two have done an awful lot of damage to our car,” said the clearly furious Mercedes man. “They’re just too aggressive… That’s tens of thousands or hundreds of thousands of pounds worth of damage by going three-foot too wide.”

Red Bull Team manager Jonathan Wheatley also complained about the “shed-load of damage” caused by the off-road undulations in the afternoon.

LE CASTELLET, FRANCE - JUNE 18: Lewis Hamilton of Great Britain driving the (44) Mercedes AMG Petronas F1 Team Mercedes W12 on track during practice ahead of the F1 Grand Prix of France at Circuit Paul Ricard on June 18, 2021 in Le Castellet, France. (Photo by Clive Rose/Getty Images)

Hamilton has been taking the more aggressive line at Turn 5 – facilitated by the resurfacing at Le Castellet

Clive Rose/Getty Images

But, as Michael Masi replied, there’s nothing new about the kerbs at the circuit. Speaking to Motor Sport, Jarno Zaffelli, whose Dromo Circuit Design firm laid new asphalt at Paul Ricard last year, it’s not the kerbs that have become more aggressive – it is the drivers themselves.

“The kerbs are exactly the same as before,” he says of the Paul Ricard circuit, last visited by F1 in 2019. “We resurfaced and remodelled all the corners apart from up to the Mistral straight. So the asphalt is new, but the kerbs and the run-offs are the same.

“It was not possible to previously go smooth like now, with drivers using new ‘tricks’ [taking different lines to get more speed]. You’re now more confident going into corners. Before the resurfacing, it was like ‘woah woah woah’, it was wobbly. Drivers needed to have a setup that allowed you to be softer [on the suspension]. There’s more sliding, there’s less grip if you’re softer.

“Now that all the corners are flatter, irrespective of the smoothness they can generate more grip, they can make their wings more constant.”

As a result, drivers are taking more risks, getting closer to the kerbs and sometimes overdoing it – the result is a solid kerb clattering.

Related article

Zaffelli detailed the ways in which his team’s reprofiling of the circuit has helped drivers attack the circuit more, as caution is thrown to the wind. “The biggest remodelling we did was between Turns One through to Seven,” he says. “Turn Seven was previously off-camber, on camber, offcamber. Then in 30 metres this changed to on, off, on. We completely took this out, so now it’s totally off-camber.

“It is [now] easier to exit slower from Turn Seven and more difficult to lose the car, but this therefore means you have more confidence to overtake in Turn Eight.”

Zaffelli believes short term memories might be contributing to teams complaints about the “aggressive” kerbs.

“[Maybe it’s] because they don’t remember, as last year F1 was not at Paul Ricard, or perhaps its because they are used to other the tracks that are more gentle on the kerbs,” he comments.

Like the high abrasion off-circuit asphalt, the design of the heavy kerbs is unique to Le Castellet.

They are known as ‘Gurdjians’ in the circuit design industry, named after Phillipe Gurdjian, the former race driver and motor sport promoter, who took over the circuit to turn it into it the ‘Paul Ricard High Tech Test Track’.

TOPSHOT - Mercedes' Finnish driver Valtteri Bottas drives during the first practice session at the Circuit Paul-Ricard in Le Castellet, southern France, on June 18, 2021, two days ahead of the French Formula One Grand Prix. (Photo by CHRISTOPHE SIMON / AFP) (Photo by CHRISTOPHE SIMON/AFP via Getty Images)

Bottas has been taking an alternate line to Hamilton – Mercedes engineers have been exploring the opportunities the new surface offers


“Paul Ricard is different in many respects to other circuits,” Zaffelli says. “When we became involved in the beginning, the idea of improving overtaking was proposed, but we tried to make subtle differences and modification rather than big ones [such as changing kerbs].”

One of the changes with the most obvious knock-on effects of Zaffelli’s redesign is the new ‘crown’ (a slight bump) installed at Turn Five.

Related article

“The reason [we were asked to install this] is because initially it [the asphalt] was very flat and a lot of water was standing there,” Zaffelli explains. “And there were no overtaking manoeuvres there, they were only happening at Turn Eight. So what we decided was to just build a proper crown there, to have the water going on the right-hand side.

“If you look at the cars going there now, you can see that some are lifting the right wheel in the air by a certain number of centimetres, depending on the setup of the car.

Zaffelli says as a result, driver skill can now displayed in a more obvious manner – and there’s one team which is getting the best out of it.

“Now, if you are good enough to stay outside Turn Four, you can go into Turn Five to avoid that sort of a jump,” Zaffelli explains.

33 VERSTAPPEN Max (nld), Red Bull Racing Honda RB16B, action during the Formula 1 Emirates Grand Prix de France 2021, 7th round of the 2021 FIA Formula One World Championship from June 18 to 20, 2021 on the Circuit Paul Ricard, in Le Castellet, France - Photo Marc de Mattia / DPPI

More overtaking could be on the cards with Dromo’s changes

Marc de Mattia / DPPI

“If you look at Hamilton and Bottas and the lines they’re doing [into Turn Five], they’re trying different lines because the Mercedes engineers understand the difference before and after [the resurfacing].

“You can see they’re trying to understand how to use the crown in different ways. When overtaking, you can either [stay outside the crown and] improve the steering of the car because you are unbalancing and using it just to make an oversteer, or you stay on the inside of it and make a ‘block pass’, because anyway you are faster if you stay inside.

“It’s very important in the race or the ‘battle’. When a track is done properly, in the end it’s up to the driver to exploit the opportunities. This will be magnified a lot at Zandvoort [also reprofiled and resurfaced by Dromo].”