The Formula 1 and Pirelli teams had no warning about the “painted” surface of the Shanghai circuit.

Because the F1 teams had done a lot of pre-event work in the simulator based on information from both Pirelli and the FIA, they were discovered when they arrived at the track on Wednesday by a distinctly different track surface.

While drivers said the track looked like it was “painted,” it turned out it was actually a liquid bitumen surface treatment applied last year to help reduce deterioration of the old asphalt.

As the track has been used since then, elements of this treatment have worn away on the racing line, giving the surface a two-tone appearance.

But apart from looking different, the treatment has affected grip levels, particularly with the contrast between areas where the bitumen stays in place and areas where it has worn away.

While the FIA ​​normally informs teams before the weekends of any material changes to the track, no notice about this transaction was included in the documents sent to the teams and Pirelli.

Furthermore, Pirelli usually sends engineers before a Formula 1 meeting to provide updated data on track conditions, but that was not done this time because the Italian company did not have any Formula 1 staff available to do so.

The problem only appeared when it arrived at the track on Wednesday with its engineers, raising some surprise.

Asked how far the FIA ​​had been communicating about the treatment, F1 chief engineer Simone Pera said: “We didn't get any indication, so we were also surprised.”

“We noticed it on Wednesday when we were inspecting the usual track, and it was quite clear that this surface was very different from the old surface.”

Motorsport.com has learned that the issue of the lack of a caution on the roof was discussed during a team principals' meeting on Friday morning with Formula One racing director Niels Vettich.

Sources state that while Wittich admitted that he was aware of the work being done, he did not consider it necessary to inform the teams as it was not a change that was supposed to materially affect the level of performance of the track, nor did it require any change to homologation.

While the changes in control were certainly not severe enough to have a bad scenario at Turkey 2020, Pera added that in the future it was clear that circuits would have to make it more clear, especially with the FIA, of the impact of any works undertaken in Formula One. 1. Places.

When asked what went wrong with communication on the issue, Pera said: “I think you need to ask the FIA, but the change of course is not what needs to be re-validated or verified by the FIA.

“This was done by the Chinese circuit management, and they could have done it without informing anyone.

“But I would say it's not the end of the world in the end because in FP1, for example, the grip level improved after a few laps, and then the drivers were able to complete the session.

“I think that in the future, the FIA ​​will try to work more closely with the circuit to understand this kind of information in advance.”

The surface treatment issue will disappear in 2025, with Shanghai scheduled to undertake a complete repaint this summer ahead of next year's race.