Why Bottas changed three tyres at his last stop in Bahrain
Mercedes Formula 1 driver Valtteri Bottas finished a lowly eighth in Bahrain after a tricky race that saw him make three pitstops – including one where he changed only three tyres.
It was the Finn's second consecutive disastrous Sunday after his 14th place in the rain-affected event in Turkey, where he spun six times.
Mercedes went into the race with less of a safety net than rivals, as both Bottas and teammate Lewis Hamilton had one set of hards and two sets of mediums left, while most of their rivals had a second set of hards
Bottas got away badly at the original start and was thus fourth when the race was red-flagged.
He took the second start from that position, but had to pit immediately with a right front puncture picked up close to the Romain Grosjean crash site.
"Apparently I picked up the puncture between Turns 3 and 4 on the opening lap on the second start," said Bottas. "For me everything looked clean, I didn't see any debris so it was quite surprising."
In effect that set of medium tyres, on which he had qualified, appeared to be wasted, and the team knew its options were limited.
Bottas made that unplanned stop under the safety car, and then ran hards for the opening part of the race, hoping that it would be possible to make only one more stop.
However, the hards did not last as well as had been anticipated as the Finn was constantly fighting his way through traffic.
"Actually the first stint when I was on the hard tyre we aimed to go for one-stop at that point," he said. "Because we knew in theory it could be possible.
"But with the amount of fighting I had to do and pushing to get through the cars we saw that it was not possible, or if sit behind them and lose chunks of time.
"So it was tricky really to find the optimal thing to do, and in the end we had to do two stops, especially when we went to the medium tyre.
"The main issue was really that in the beginning there was a big train of cars all with DRS, and everyone knows it is not easy in this kind of situation, you really have to push a lot and slide around behind other cars if you want to make positions, and that way you lose tyre life. So it was not easy."
He took a set of mediums at his stop on lap 25, and then pitted again on lap 38.
Rather than go to the unfavoured softs, the team took the opportunity to re-fit the medium set that he had run in qualifying and at the start of the race, but without the punctured right front – and thus he kept the well-used tyre that was already on that corner.
"The medium we put on at the end, we actually only changed three tyres, and it was not that old, only a few laps. The first 10 laps in the last stint felt OK, but we had some overheating.
"The drivers and cars with the hard tyres on could keep going for quite a bit longer and still able to push harder without overheating. For me the hard tyre was better."
In the closing laps he had a second puncture when running under the safety car, but fortunately he was able to cruise to the finish line without an extra stop.
"At the very end during the safety car there was another puncture on the rear tyre, I think it was rear right, and again I didn't see anything at any point.
"Obviously there was quite a bit of debris around, but some of it you can't really see it. So another unlucky race for me."
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