Pirelli is investigating cause of unusual tyre 'waves' that caused damage to Lance Stroll's car.

Slow motion footage of the rear of the cars in the final chicane revealed 'waves' rippling across the rear tyres, a phenomenon not witnessed before.

Indeed, it is being claimed that the vibrations caused the damage to Stroll's rear wing which prevented him making it through to Q2.

"We are looking at what they can be or which is the type of stress on the tyre," Pirelli's Mario Isola told Motorsport.com, admitting that he had never witnessed anything like it before.

"At the moment I don't have a lot of information because we are working together with the teams to better understand this effect," he admitted. "It seems that we have this at the exit of the bus stop, and exit of Turn 1, so slow speed corner in traction.

"We have to better understand it. It could be an effect of the grip with the torque. Obviously the grip this year is much higher and the tyre is wider, so it could be a deformation of the contact patch and the torque that generates these vibrations. We are now looking at the data from the teams in order to better understand this effect."

Asked whether this might necessitate set-up changes, he said: "This is why we are interested to better understand why we generate this vibration and what are the possible consequences.

"What we have asked the teams is can we work together a bit to better understand which is the dimension of this vibration, the extension in time and the construction. And when we have something more, probably tomorrow (Sunday) morning, then we can take a decision. So far it is difficult to say if we are obliged to take any action."

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