There's been a lot of talk about tyres so far in the 2018 Formula 1 season, but during the Spanish Grand Prix weekend a combination of Mercedes getting back on top and a change in the Pirelli tyre specification prompted even more of it.
Pirelli's decision to reduce the tyre gauge (the tread thickness) is something that can have a major influence on how tyres behave and warm up, and how they hold that heat. It's another learning curve for the teams, so the question is: did this help Mercedes, and why?
Reducing the gauge of the tyre is mainly to reduce the risk of the kind of blistering encountered during pre-season testing. It is the rubber content that retains the heat in the tyre, and once this reaches a critical level the rubber starts to form liquid pockets, like blistered skin. Even if it's not visible, you can still get internal blistering.