Tyre degradation

Thermal vs mechanical

• Thermal degradation happens when a tyre exceeds its optimal operating temperature window. The rubber compound breaks down chemically, losing grip even if the tread looks healthy. This is reversible up to a point: cooling the tyre by lifting and coasting can recover some grip.
• Mechanical wear is the physical loss of tread rubber. It is irreversible. As the tread thins, contact patch shape changes and grip drops permanently.

In a normal stint both happen simultaneously, but their balance depends on compound, track surface, and weather^[1].

The cliff

The "tyre cliff" is the point in a stint where lap times stop degrading gradually and start collapsing suddenly. A tyre might lose 0.1 seconds per lap for ten laps, then lose a full second per lap for the next three. After the cliff, the tyre is unable to maintain competitive pace and the car must pit immediately.

Cliff onset varies by compound:

• Soft compounds (C5, C4) cliff earliest and most dramatically.
• Medium compounds (C3) have a gentler degradation curve.
• Hard compounds (C2, C1) degrade most slowly but warm up slowest^[1].

What drivers do to manage degradation

• Lift and coast at corner entry to reduce front tyre temperature.
• Take wider lines to load tyres more evenly.
• Manage throttle on corner exit to limit rear tyre slip.
• Conserve in a stint when fighting for a one-stop strategy.

What teams model

Pre-race, teams build a tyre model for each compound based on long-run pace from Friday practice. The model predicts degradation rate per lap and cliff lap for each driver and compound combination. The model is updated continuously during the race as actual stint data arrives.