Pirelli’s C5 compound is no longer the softest of the range, with the F1 tyre manufacturer set to debut the C6 at this weekend’s Emilia Romagna Grand Prix.

Aside from their two wet-weather compounds, Pirelli have a range of five slick compounds and they give the teams three to use at every Grand Prix depending on the circuit.

Pirelli: It’s hard to imagine…

From the C1 being the hardest compound to the C5 being the softest, the three compounds available each weekend are labelled hard, medium, soft, whether they are on the harder side of the scale or the softer.

But this weekend at Imola, when Pirelli say soft, they mean extremely soft – the C6.

Pirelli announced last year that they would design a sixth tyre compound for the F1 2025 championship, aimed at improving the racing by forcing teams into additional pit stops.

“We are already planning to go softer for next year, to introduce a C6, a softer compound especially for street circuits,” said Pirelli motorsport director Mario Isola.

Mike Krack, now Aston Martin’s former team principal, said at the time that introducing a C6 would be worthwhile “because I think it opens up additional strategic options.

“Whether it will be [nominating] C6, C5, C4 or C6, C4, C2 or stuff like that, that is obviously for [Pirelli] to choose. But I think with the cars staying the same [for] the final year of the regulations, I think adding some variation there, we welcome that.”

F1 2025: The season’s winners and losers

👉 The results of the F1 2025 championship

👉 The updated Drivers’ and Constructors’ Championship standings

Seven races into the F1 2025 championship, the C6 will make its debut at the Emilia Romagna Grand Prix.

Last season, Pirelli put their softest range on the track at Imola with Max Verstappen winning from pole position ahead of Lando Norris and Charles Leclerc. Despite the track temperature hitting 50 °C, the hard tyre worked best as the majority of the field ran a one-stop strategy.

This weekend, with the C6 in play, it’s hoped that it will force the drivers into two-stop strategies and break-up the traditional one-stopper at Imola.

‘The new C6 compound will make its race debut in Imola, as Pirelli has chosen the softest trio of compounds in its 2025 range for this weekend, with the C4 as Hard, the C5 as Medium and the C6 as Soft,’ read the Pirelli statement.

‘It will be the first time that drivers will run the C6 on this season’s cars as none of them used it in the Bahrain test.

‘Homologated for use at tracks that stress the tyres the least, the C6 could provide even more grip over a flying lap, especially as the Imola surface is less abrasive than average.

‘It’s hard to imagine it being used for a race stint, but data gathered in Imola and then from Monaco and Montreal, will allow the Pirelli engineers to evaluate it for other Grands Prix in the second part of the season.’

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