Valtteri Bottas gains valuable F1 mileage ahead of Cadillac return
Valtteri Bottas took in 112 laps in Mexico City as part of a tyre test.
Valtteri Bottas has completed 112 laps of the Autodromo Hermanos Rodriguez as he undertook Pirelli tyre testing with Mercedes.
This is another step towards his Formula 1 comeback with Cadillac next season, with the Finn set to partner Sergio Perez at Formula 1’s newest team in 2026.
Valtteri Bottas completes F1 2026 tyre test with Mercedes
Bottas reverted to a reserve role with his former team after he was left without a place on the grid for 2025, but has found a route back to Formula 1 with Cadillac next season, with he and Perez set to form one of the most experienced partnerships in the field.
This run at the home of the Mexico City Grand Prix may have yet been the final laps he has driven in a Mercedes Formula 1 car, but PlanetF1.com understands the team’s plans are currently not yet set as to whether or not he will conduct any further testing this year.
Bottas joined Mercedes junior, Frederik Vesti, in testing multiple new Pirelli compounds for the 2026 season, behind the wheel of a mule car provided by the Silver Arrows.
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Bottas spent the majority of his day testing the new C3 tyre – the most-used compound in Pirelli’s range – with a series of long runs that saw him eventually take in just over one-and-a-half race distances around Mexico City.
Construction is changing significantly for Formula 1’s tyre manufacturers next season, with teams having taken part in separate tests all season as Pirelli looks to finalise its 2026 compounds.
The 18-inch wheels are being retained for 2026, but the tyres will be reduced in width by 25mm on the front and 30mm at the rear, offering a smaller surface of grip with which the drivers will work next season.
Vesti took in several 10-lap runs on his way to 49 laps on the day, helping Pirelli gather more data for its tyres next season.
Bottas has taken part in several behind-closed-doors tests so far this year, doing so with McLaren back in March before undertaking a private Mercedes test at Jerez in July.
The final Pirelli tyre test of 2025 will take place in Abu Dhabi on 9 December, two days after the 2025 season finishes.
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