The 2025 Chinese Grand Prix brought unexpected drama as Ferrari’s Charles Leclerc and Lewis Hamilton, along with Alpine’s Pierre Gasly, faced disqualifications. While Leclerc and Gasly were penalized for finishing 1kg under the 800kg minimum weight requirement, Hamilton’s exclusion stemmed from his underbody plank being 0.1mm below the legal threshold. These infractions raise important questions about Ferrari’s SF-25 design and whether it presents an inherent setup challenge.
Weight Exclusions and the Fine Margins in Racing
Leclerc and Gasly’s weight infractions resulted from an unforeseen consequence of race strategy. Initially, high front tyre graining suggested a two-stop strategy would be optimal. However, as the track rubbered in, degradation rates dropped, allowing teams to switch to a one-stop approach. This shift led to extended stints, with Leclerc running 41 laps (73% of the race) and Gasly 46 laps (82%) on their final set of tyres.
The impact of prolonged tyre use is significant: worn tyres can shed up to 8-10kg, primarily due to tread wear. Given the impossibility of precisely predicting tyre mass loss, Ferrari and Alpine may have underestimated the final car weight, leading to the post-race penalty. Teams typically avoid adding excess ballast to account for worst-case scenarios, as even 5kg extra can cost nearly 0.195s per lap. Over 56 laps, this could amount to an 11-second deficit—an unacceptable trade-off in a competitive field.
Hamilton’s Plank Wear Issue: A Deeper Problem?
Unlike Leclerc’s disqualification, Hamilton’s exclusion was due to excessive wear on the underbody plank. Running the car as low as possible is crucial for maximizing downforce, but Hamilton’s Ferrari exhibited noticeable floor sparks early in the race—an indication of aggressive ride height settings.
Interestingly, Hamilton opted for a two-stop race with a final stint of only 19 laps. This likely helped him avoid a weight-related exclusion but did not prevent the plank wear issue. The problem may be symptomatic of Ferrari’s unique SF-25 design.
SF-25’s Potential Setup Challenges
Ferrari’s 2025 challenger, the SF-25, features a notable design evolution: a cockpit positioned further back relative to the front axle to enhance airflow management. However, this shift necessitated a 5cm reduction in gearbox length, moving the deepest part of the gearbox closer to the rear axle. This positioning could lead to more pronounced ride height variations, affecting aerodynamics.
Moreover, Ferrari appears to be employing a slightly higher rear ride height compared to its rivals. This design choice, combined with a softer rear suspension setup, enhances mechanical grip—helping Ferrari’s impressive performance in slow corners. However, the greater ride height at low speeds can reduce diffuser effectiveness. Ferrari has attempted to counteract this with a unique diffuser lip, which may become overly effective as the car compresses at high speeds, exacerbating plank wear.
Hamilton’s Sunday setup changes, which he admitted ruined the car’s balance, may have worsened the issue. Meanwhile, Leclerc, despite sustaining front wing damage, remained faster—potentially indicating a lower ride height setting. If true, this might have increased rear downforce but also contributed to the plank’s excessive wear.
A Growing Concern for Ferrari?
Ferrari’s disqualifications highlight the razor-thin margins in modern Formula 1. While tyre wear miscalculations explain Leclerc’s penalty, Hamilton’s issue could indicate an ongoing challenge in balancing the SF-25’s aerodynamic concept. Finding the optimal ride height and suspension settings without compromising durability could be a key factor in Ferrari’s championship aspirations.
As the season progresses, Ferrari will need to refine their setup strategies to avoid future penalties and ensure that their strong performance does not come at the cost of regulatory compliance. With the field as competitive as ever, even the smallest misjudgment can make the difference between victory and disqualification.
