Over the winter, teams were warned that stricter tests would be introduced. The rear wing rules were already enforced at the Australian Grand Prix, while the front wing changes will come into effect at the Spanish Grand Prix in May.

After reviewing data from the Melbourne race, the FIA found that teams were still able to flex their rear wings more than allowed. To fix this, the maximum gap between the mainplane and the rear wing flap will be reduced from 2mm to 0.5mm when a 75kg load is applied.

Even though all teams passed the initial flexibility tests in Australia, the FIA decided more changes were needed. It has now confirmed that the new rear wing rules will apply from the Chinese Grand Prix, with further tightening planned for Japan.

For this weekend’s race in Shanghai, the new 0.5mm limit will already be in place. However, because the rule change was announced on short notice, a small extra allowance of 0.25mm will be permitted. The decision comes after video footage and inspections showed that previous changes did not fully solve the “mini-DRS” issue from last year.

The full statement reads:

"As has been previously communicated, between the end of the 2024 season and the start of the 2025 season, the FIA exercised the authority it is granted under Article 3.15.1 of the Technical Regulations to introduce either new or more challenging load-deflection tests for the front wing (from Race 9, Spanish Grand Prix), the upper rear wing, and the beam rear wing. In addition, the FIA requested to the teams to use cameras in Free Practice Sessions to monitor the on-track deformations exhibited by the cars during the Australian Grand Prix.

"Having analysed footage from the rear wing deformations combined to the static deflections measured inside the FIA garage in Melbourne, the FIA has concluded that sufficient grounds exist for a tougher test to be introduced from the forthcoming Chinese Grand Prix on the upper rear wing.

"More specifically, Article 3.15.17, introduced in 2025, states that if 75Kg of vertical load is applied on either extremity of the rear wing mainplane, the distance between the mainplane and the flap (also known as “slot gap”) must not vary by more than 2mm. From the forthcoming Grand Prix in Shanghai, this limit will be reduced to 0.5mm. Due to the short notice for Shanghai only a tolerance of 0.25mm will be added to this new limit.

"The Teams were informed of this revised test early Monday 17th of March.

"The FIA wishes to further confirm that during the Melbourne event all cars tested against the requirements of Article 3.15.17 and found to comply, therefore all cars raced in Melbourne were deemed to be legal."