Lewis Hamilton, Mercedes, Paul Ricard, 2021

How Rosberg’s theory about Hamilton’s chassis change was refuted

2021 F1 season

Posted on

| Written by

Mercedes’ decision to swap the chassis being used by Lewis Hamilton and Valtteri Bottas at this weekend’s race prompted speculation over its cause and effect.

As Bottas endured a poor weekend at Azerbaijan, and Hamilton lagged behind him in the opening three practice sessions at Paul Ricard, some wondered whether the world champion had been left at a disadvantage. The results of qualifying, where Hamilton beat Bottas to second on the grid, silenced that suggestion.

The opposite view, that Hamilton stood to benefit most from the change, was espoused by the team’s former driver Nico Rosberg during the build-up to the race on Sky.

“I think Valtteri’s chassis was the younger one because he changed after Imola,” Rosberg claimed.

“He got a fresh chassis there, so Lewis’s chassis had a lot more miles on it. Lewis wasn’t feeling comfortable, especially in Monaco.

“So from my point of view, it was Lewis saying in the team ‘hey, I want to try Valtteri’s chassis, I want to see if there’s something wrong with my car and see if I can find some extra performance’. I think he was pushing for it.”

Adding fuel to the fire, Rosberg claimed this was never done during his seven-year stint with the team alongside Hamilton and his predecessor Michael Schumacher.

“We would never switch chassis between drivers,” said Rosberg. “If I would feel bad, I might push for a new chassis, but never to get the chassis of a team mate. This, for me, is an indication also that they are really trying to give a little bit more of a preferential treatment to Lewis than usual, which is understandable. He is in that straight fight with Verstappen, so he needs all the help he can get.”

Advert | Become a RaceFans supporter and go ad-free

While some teams guard the details of which chassis their drivers are using, Mercedes routinely disclose who is using which tub at each race. Therefore Rosberg’s claim could be quickly disproved: He took over W06 chassis one at the end of 2015, which Hamilton used at the beginning of the season.

Nonetheless the suggestion Mercedes were handing Hamilton an advantage struck a chord with many, and Rosberg’s comments were widely regurgitated without question.

When Hamilton emerged from his car after qualifying second yesterday, he took Sky’s Paul di Resta to task over how the chassis change had been covered. “I saw you coming up with some myth and I’m happy to be able to prove it wrong,” he said, adding “all the cars are exactly the same.”

“I heard yesterday that Paul was saying something about the chassis,” he explained in the press conference afterwards. “I think he said there was a press release… I don’t know. And then just creating the question about whether our chassis were the same et cetera.

“As you can see, today I managed to do a great job with the same car, so it’s no different.”

Like their rivals, Mercedes are racing chassis which are based on those which were used last year, and therefore began the season having covered different mileages, as Mercedes CEO Toto Wolff explained on Saturday evening.

Advert | Become a RaceFans supporter and go ad-free

“We have four carry-over chassis,” he said. “The other big teams, Ferrari and Red Bull, they should also have carry-over chassis rather than producing a new one, because a new one would be too expensive.”

Bottas’ crash at Imola led to him being given a different chassis. He took over number four while Hamilton continued with six. Those were exchanged this weekend – so the lower-mileage chassis transferred from Bottas to Hamilton – and a repaired number five chassis from Imola will return at a later stage in the season.

More importantly, the tests teams subject chassis to leave little to no room for differences, a point surely underlined by Hamilton’s qualifying performance yesterday.

“In the modern day and age, those chassis come back to the factory, they are laser scanned,” Wolff explained, “They are checked for stiffness and T&D” – test and development, a department within the team.

“These were all chassis that won races over the last few years, chassis that now have been utilised by everybody, by both drivers,” Wolff confirmed. Whether that explanation will satisfy his former employee remains to be seen.

2021 F1 season

Browse all 2021 F1 season articles

Author information

Keith Collantine
Lifelong motor sport fan Keith set up RaceFans in 2005 - when it was originally called F1 Fanatic. Having previously worked as a motoring...

Got a potential story, tip or enquiry? Find out more about RaceFans and contact us here.

10 comments on “How Rosberg’s theory about Hamilton’s chassis change was refuted”

  1. Nice to see the question, as well as the answer, for a change…

  2. Now nobody can trust Rosberg anymore.

  3. Rosberg left in 2016. He sounds like a bitter ex.

    1. Sometimes a little bit, though he also often is very pro-Merc, and even Hamilton to me; interestingly one could argue the lower milage chassis to HAM might be a teensy bit of a benefit (even though indeed BOT had that for a few races after his old one got trashed in imola; if both chassis’ are running, and they are the same, what does it matter who is in it otherwise? But whatever, probably not much in there).

  4. Ooh, RaceFans took this one seriously. Can’t come up with anything against the favorite.

    Rosberg saying they didn’t switch chassis and Keith going straight to dig up the data of all those races years ago to fact check it, is quite something as this must have takensome effort, especially compared to all sorts of other claims that are let through without a single thought. But they are not directed in the same way of course.

    And does Rosberg not mentioning the time the chassis was switched mean it was standard practice as opposed to what he was saying, as or was it him forgetting the single instance? I think the answer is obvious. And would it any way take away from his point that this could indeed be to hand Hamilton an advantage? What if he had asked for the chassis change, suspecting something was wrong with it as he’s done in the past, and the team thought the best way was a straight swap? Why were the chassis swapped in the first place?

    1. Hazel & Will are reporting on the races.
      Dieter is doing the investigative and insightful teams and FIA stories.
      Keith has got Lewis’ back.

  5. I actually am a bit baffled by the title of the article – There really is nothing that actually really refutes this theory in the article as far as I can see.

    Sure, Mercedes talk about how this was planned anyway. It might be that they had planned that chassis 6 to be used by Hamilton now and have Bottas stay on chassis 5 if that had not been wrecked. But why would they tell us about any of this (and give Max a nice one to dig into with a snarky comment?) even in case it was not planned all along.

    That in general these chassis get used as seen fit by both drivers over sets of races and that they tend to be more or less the same (as far as teams can make sure) does not mean that a drivers’ mind cannot be affected by the idea that it somehow does matter. Bottas certainly acted as if he was happy about the change. And Hamilton even reacted to that after qualifying. So it clearly does matter at some level.

    1. @bascb I guess there are two separate issues: one, whether the chassis change was ‘programmed’ and not made or anticipated for Lewis’s benefit (as Rosberg implied) and two, whether it makes any difference. Based on the relative performances and feedback of the drivers, the answer to the latter has to be ‘no’. They’ve both had good and bad races, qualifying sessions, or practice sessions, on both chassis. But like you say the answer to the first issue isn’t really answered (or disproved). I was kind of surprised by Hamilton picking up on the chassis coverage on Sky so emphatically, but didn’t know about the Rosberg angle. That totally explains why!

  6. someone or something
    21st June 2021, 0:19

    Rosberg’s comments were widely regurgitated without question

    Translation to English:
    At least two people agreed with him on Twitter, and it made me furious.

    Talk about a thin skin …

  7. He’s wrong about everything. I’ll never forget what Verstappen said about Rosberg at Monza 2019.
    At least he’s still right about Baku.

Leave a Reply

Your email address will not be published. Required fields are marked *

All comments are moderated. See the Comment Policy and FAQ for more.
If the person you're replying to is a registered user you can notify them of your reply using '@username'.