The one area where McLaren was "genuinely struggling" in F1 pre-season testing

While McLaren's baseline form over the early part of the 2025 Formula 1 season had been strong, any weaknesses that emerged in the year's nascent stages appear to have been ironed out with development.

The team has secured 1-2 finishes in each of the last four races, putting it 299 points clear of Ferrari in the constructors' championship with 10 rounds remaining. If it continues that form, it could have the teams' crown wrapped at the Azerbaijan Grand Prix.

Race pace has scarcely been in doubt, thanks to the MCL39's light touch with tyres and consistency over longer stints. It has also helped that its top-four rival teams have endured fluctuating form; Ferrari, Mercedes, and Red Bull have ebbed and flowed through the year.

While both drivers have been able to secure pole positions and front-row lockouts with the 2025 car, qualifying performance has been its weaker trait. The MCL39 does not present the same high-wire act as, say, Red Bull's RB21, but both drivers have expressed their difficulties in getting the car to dance to their tune on a single lap.

"I think in testing in Bahrain we had some concerns about not necessarily the steering or the front suspension, but just the car was very tricky to drive on the limit in testing," Piastri explained in an exclusive interview with Motorsport.com. "Our race runs were always very strong, but in the kind of qualifying sims, we were genuinely struggling.

"We had a lot of work to do to try and unlock that. And I think you've still seen kind of episodes of that through the year. Canada for example, a few other tracks where it has been quite difficult to drive on the limit and that's probably been the thing we've been most vocal about, partly because everything else has been so good."

Oscar Piastri, McLaren

Photo by: James Sutton / Motorsport Images

In the early part of the season, Lando Norris was particularly vocal about this - and the numbness that team principal Andrea Stella confirmed that both drivers had felt was one of the reasons why the team produced a variant of its front suspension package.

This suspension package variant has offered a change in the overall caster angle (the angle between the upper and lower suspension joints, effectively the steering alignment), which in turn will require a change in kingpin inclination (the angle between upper and lower suspension joints, but viewed front-on).

In doing so, there's a self-aligning torque associated with the wheels while the driver steers, something that offers greater feedback. Norris, who perhaps has more value on the feedback through his hands versus those who perhaps feel the car through their lower back, has thus benefitted from this.

There are downsides to doing so, and increasing caster also increases the steering effort required to turn - although this is less of a consideration when it comes to F1 cars and their power steering systems. But there's also the effect of dynamic changes to other kinematic variables to be aware of; in cornering, for example, caster is not independent of camber, which can change how the car behaves.

Mclaren MCL39 technical detail

Photo by: AG Galli

While Norris has taken that suspension package, Piastri has not. He feels he does not require the change in feedback at the steering wheel, and has not wanted to change the way the car feels in the same way that Norris has.

Although he's been the quieter of the two drivers on the subject, Piastri clarified his thoughts on the MCL39's handling - and felt that, unlike Norris, he was able to mitigate his greater qualms with set-up.

"I've not really struggled with that feeling or sensation," Piastri offered. "We've tried different things with the front suspension to see if it changes much. But for me I've been pretty happy with how it's been.

"For me it's not been a big concern, but definitely I still shared initially anyway the kind of same feelings about the car being pretty difficult to drive in some conditions.

"I think we've done a much better job of addressing that with set-up and also just for me expectations and getting used to the car more. But there's not really a specific trait that I don't like anymore."

Watch: Oscar Piastri Exclusive: From Rookie to F1 Title Contender in His Own Words