Ferrari’s mission in Sakhir: rear-end stability and overheating management. Ferrari SF-25 Development: Stability Struggles and Thermal Management.

Ferrari was not perfect. On the contrary, during the fourth Friday of the 2025 Formula 1 season, many things did not work for the Maranello team. First of all, it must be said that with the new floor there was a need to experiment. Moreover, the first free practice session at the 5.412-kilometre Bahrain International Circuit in Sakhir was almost useless due to the dirty track, not to mention the tire overheating and the setup of the Italian car which, with a different weight distribution, was not easy to get right.

Once again, McLaren confirmed itself as the car to beat over a single lap. In FP2 in Bahrain, Oscar Piastri put a full 0.527 seconds on the first chasing car, which was George Russell’s Mercedes, and 0.540 seconds on Charles Leclerc, who finished fourth. The MCL39 seemed precise, balanced, and especially capable of generating grip in every phase of the corner, dominating every sector and building its main advantage in Sector 2, where it gained 0.327 seconds on its rivals.

Charles Leclerc, for his part, showed an SF-25 that was not particularly well-balanced and unable to deliver top performance over one lap. The front end seemed fairly responsive, and the chronic understeer that had afflicted the car in previous GPs remained—though milder—combined with slight oversteer on corner exit, especially coming out of turns 13-14. But the main puzzle remains the behavior of the rear under traction.

The direct comparison with Oscar Piastri begins already in turn 1, where Charles Leclerc brakes slightly later but still manages to decelerate effectively, enough to get back on the throttle at the same time as the Australian. In this part of the track, one of the most crucial elements in braking management is without doubt the brake balance, namely the distribution of braking between the front and rear axles.

Indeed, throughout the session, the two Ferrari drivers received radio suggestions to adjust it corner by corner, with the aim of improving braking stability and preventing lockups. Drivers can tweak the brake balance directly from the steering wheel, adjusting it to their preference. Generally, to avoid front locking, the balance is shifted slightly to the rear.

However, this adjustment must be a compromise: too much rearward braking can destabilize the car or cause rear locking. Finding the right compromise between front and rear is one of the keys, especially for Charles Leclerc, given his choice to modify his braking style in an attempt to improve his performance.

Moving on to the S-bend of turns 2-3, Oscar Piastri manages to go full throttle earlier, building up speed for the following straight. Charles Leclerc, instead, modulates the throttle more cautiously, reaching 100% throttle slightly later. Then comes turn 4, a corner where the SF-25 struggled to hit the apex during pre-season testing, but today the situation is different. The Monegasque driver works to mitigate possible understeer on entry.

He does so by braking a few meters earlier, setting up the corner entry optimally, hitting the apex perfectly, and even going through it with a 10 kilometers per hour delta over the Australian driver. This shows a significant step forward for the Ferrari. However, on exit, Charles Leclerc is a bit late on the throttle, as the rear still needed a few more meters to settle and complete the final phase of the corner smoothly.

In corners like this, but also in 8, 10, and 14, the dampers come into play—the shock absorbers. On a track like Bahrain, the load transfer between braking and traction must happen very quickly. A fast compression of the rear is needed to ensure grip for the driven wheels, and a fast decompression of the front to release the load and facilitate the transition.

If the dampers—referring to the F1 car’s shock absorbers—do not respond optimally, then the load is not transferred quickly enough, and traction cannot optimally transfer all the engine’s power to the ground. And this is exactly what was missing on corner exit from turn 4 on car number 16, an aspect that cost small fractions of a second compared to the impressive McLaren.

Even in the snake section, namely turns 5-6-7, the Ferrari SF-25 car holds its own against McLaren, with Charles Leclerc taking turn 6 at 9 kilometers per hour more. However, he again loses something in turn 7, where he lifts off too much, perhaps to manage the oversteer during roll. From turn 11 onward, the MCL39 begins to pull ahead: in this very fast corner, where one enters at 300 kilometers per hour and takes it at 162 kilometers per hour, the British car shows excellent balance.

It sticks to the track surface without needing to correct the steering even by 1 millimeter, but most of all, it manages to go full throttle many meters earlier than the Ferrari. This translates into a gain of about a tenth and a half. Even in turn 13, Oscar Piastri finds much more grip, especially on exit, where the car from Maranello, after a good entry onto the innermost curb, makes small corrections to tame the rear.

Even here, the gain for the papaya-colored car is considerable. Without a doubt, this time loss from mid-lap onward is attributable to the much-discussed overheating that affects all cars, as Ferrari team principal Frederic Vasseur himself confirmed in interviews. McLaren suffers less, as it manages temperatures better with a more efficient aerodynamic package.

When the track surface is too hot, in fact, the tire tends to lose grip and the rear becomes unstable, especially in long, fast corners. In short, the SF-25 is making progress, but the behavior of the rear, between mechanical and thermal setup, remains a critical issue. McLaren, on the other hand, once again appeared very solid in every area, able to find grip where others are clearly struggling.

— see video above —