Formula 1 teams need to be "responsible" with tyre stint length

Lewis Hamilton, Valtteri Bottas and Carlos Sainz Jr all suffered front-left failures in the closing laps of the British Grand Prix last weekend after pushing their C1 tyres for an unusually long stint due to an early safety car intervention.

Pirelli has upped the minimum front pressures by 2psi and the rears by 1psi as a precaution for this weekend's race at Silverstone.

In addition Pirelli believes that the move to a one-step softer range - with the C2, C3 and C4 now in play - will push teams toward two-stop strategies, automatically ensuring shorter stint lengths.

However it has not mandated any maximum stint lengths, and there remains a possibility that teams will try a one-stopper involving a long stint on one of the compounds.

Isola (below) admits that Pirelli is relying on the teams not to push the limits of tyre life.

"Yes, I am worried because I don't want to see any tyre that fails on track. That is a priority, so we all need to pay attention," he said.

"What we can do from our side is to give as much information as we can to the teams in order for them to run our product in a safe way. If they take a risk, they take risk, we cannot stop anybody, we cannot jump on track and stop a car, for sure.

"So I hope they will be responsible, knowing what happened last Sunday, not to do something above the limit.

"That is why we decided to avoid any mileage limitation. I trusted the teams, I trusted their ability and they are professional, and they know what to do.

"I am sure they will not take any risk. But in F1 as in any other motorsport championship, if you go above the limit you risk a failure. It's the same with a car. If you take the engine at the rev limiter forever at a certain point, you break it.

"So it's a matter of optimising the package in the best possible way, without going above the limit. And how can we do that? By giving them any update that is useful to understand the tyres. I'm sure they will not take a risk."

Isola added that it is impossible to impose a limit on how far a given compound can run, due to each car and driver's different characteristics.

"The reason why we decided not to impose any mileage limitation to the teams is that each car is different, each driver is different, he said.

"And one of the important things in F1 now for the show is the possibility for the teams to plan different strategies.

"If we were ever to suggest or define a limitation in the number of laps for each compound it means that we bring all the teams to plan the same strategy, that is not in the target for the show.

"So what we did is to give clear information to the teams through our engineers in order to make them aware of our findings, the result of the analysis and useful information to make their plan for this weekend.

"I believe that a two-stop strategy will be the baseline for this weekend, because looking at the average numbers, it is what we found especially during FP2. But each one can decide if they want to use a mix of hard, medium or soft, or maybe move even to a three-stop strategy. Three-stop on paper is not the quickest solution."