WRC Sweden: why tyres matter
Unlike on every other WRC round, drivers only have one type of tyre available at Rally Sweden. But it's a pretty special tyre. The Pirelli Sottozero Ice J1B – as used by the Rally1 and Rally2 cars – features 384 tungsten-tipped studs. Each stud measures 20 millimetres in length, seven millimetres of which protrudes from the tread. This bites into the ice surface to provide excellent grip and make Rally Sweden's breathtakingly high speeds possible.
For the drivers, tyre management on Rally Sweden is all about maintaining that excellent grip from a single set of tyres across a full loop of stages. When temperatures rise above freezing, the gravel usually hidden by the snow and ice becomes exposed and can rip the studs from the rubber. To help prevent this, Pirelli uses a unique and patented vulcanisation process to lock the studs into place, rather than inserting them afterwards.
