Pirelli increases the minimum tire pressure to protect the tires from damaging external forces such as at the British Grand Prix. But when inflated, the tires get a little more bulky, reducing the contact area of the tire. This change is difficult to see with the naked eye but has serious consequences for a sensitive machine like the F1 car.
The consequences were even greater when it happened on the W11 – a superior car. It was capable of reaching high speeds in the corners thanks to the power of the engine and the great amount of compression. This put the tires under the load far more than the competition.
The tire overheating is something Mercedes has also predicted before the race. But they predict that the problem will be mainly with the front tires, as at the British Grand Prix. So Mercedes tried to preserve the front tires by changing the set-ups. However, the reality on the track is completely different. This caused the German team to fire by asking the drivers to slow down to keep the rear tires.
So why is the same condition, the same situation impacts Mercedes more than Red Bull?
The decision to let Bottas have a second tire change right after Verstappen also seems like a bizarre one. This caused the Finnish racer to quickly fall behind. Bottas criticized the home team after the race. However, in general, Mercedes’ choice at that time was not to compete with Verstappen but to find a way to escape the pressure from Charles Leclerc, a Ferrari driver emerging as a threat thanks to 1-pit tactics.
Moreover, the most important factor that caused Bottas to be called into the pit earlier than Hamilton was that the directors were concerned about the vibration from the rear tires of the W11. Hamilton was not subjected to the same vibrations, allowing the British driver to extend his second set of tires. In fact, despite the prolonged use of the second set of tires, even using the 1-pit tactic, Mercedes is unlikely to beat Verstappen.