Cars underweight due to tire wear: FIA implements countermeasures to prevent such incidents in 2026. A change is included in the 2026 regulation draft, which introduces a different minimum weight between qualifying and the race.

The 2024 Belgian Grand Prix and the 2025 Chinese Grand Prix have one thing in common: a disqualification for at least one car being underweight at the end of the race, something that is actually rare in F1. In the upcoming Belgian race, the disqualified driver was the winner, George Russell, while in Shanghai, Charles Leclerc and Pierre Gasly were the ones who suffered the same fate.

In all three cases, the situation is the same: a race originally planned for two pit stops turned into a one-stop strategy. The only difference is that in Belgium, only three drivers attempted the single stop, while in China, fourteen out of twenty drivers changed their strategy compared to the initial predictions.

Clearly, there are multiple factors that can influence whether a car is within the legal weight limit or gets disqualified, including the car’s weight, the “safety” margin set by the team, and tire wear, which varies between teams. The latter was the reason behind Charles Leclerc’s and Pierre Gasly’s disqualification in Shanghai, with the Monegasque losing the fifth position he had achieved on track.

It’s logical to conclude that, since the other twelve drivers who followed the same strategy were not disqualified, there was an error in the teams’ calculations and degradation estimates, though the circumstances help provide a more complete picture of the situation.

However, this scenario should not be repeated in 2026 when the cars will change with a new technical cycle that will see both the Power Units and aerodynamics completely revised. Considering what happened at Spa in 2024, a change was already included in the 2026 regulation draft at the end of last year, which introduces a different minimum weight between qualifying and the race.

Currently, the regulations require a single minimum weight valid for both qualifying and the race, set at 800 kg, including the driver (82 kg in total) but excluding fuel, which must be valid at any point during the competition. In Charles Leclerc’s case in Shanghai, the car’s weight was measured with a spare front wing due to an incident on the first lap.

For 2026, however, the regulation introduces a novelty: the minimum weight will differ depending on the stage of the weekend. In the regulation draft released last December, the text states: “During sprint qualifying and qualifying, the minimum weight is 726 kg plus the nominal tire mass. In all other sessions, the minimum weight is 724 kg plus the nominal tire mass.”

Thus, between qualifying and the race, there will be a two-kilogram difference, designed specifically to address the issues raised at Spa, with the addition of the nominal tire weight, which will be determined after the pre-season test sessions in 2026.

“To determine the nominal tire mass, the dry tire masses will be measured by the tire supplier and published after the final day of TCC (“Test Current Car”) testing before the start of the season, and it will be the average of a sample of 50 tires per axle,” states article C4.7 of next year’s regulations.

Beyond these modifications, which are specifically intended to prevent a situation like the one seen at Spa and Shanghai from repeating so easily, there is another crucial element: it will not be easy for teams to meet the minimum weight imposed by the FIA. At the dawn of a new technical revolution, teams often struggle to reach the minimum target set by the Federation, as seen in 2022 with the switch to ground effect cars.

At that time, lighter cars, particularly the Sauber, enjoyed a tangible advantage over the competition, at least until other teams also shed excess weight from their cars. However, the targets set for 2026 are probably even more ambitious than those of three years ago, aligning with the FIA’s policy, which has strongly pushed for lighter and more agile cars, especially considering the new Power Units debuting next year.

Having lighter cars is not just a goal, but a real necessity. For this reason, the tires will have a smaller diameter and will be slightly narrower than the current ones, so the weight variation between a completely new set and a used one should be reduced.