The right tire for the right conditions
The main one, which Michelin Motorsports boss Nicolas Goubert pointed out to me, and then reiterated in the press release, is that the soft tires were made for full wet conditions. The reason for bringing two different compounds of wet tires was to cope with a wide range of conditions. The soft tire was meant to deal with a track that was absolutely soaking, with patches of water. The rubber is almost as soft as chewing gum, and incredibly sticky. The hard tire is meant to help clear water from a drying track, and withstand the heat generated by a dry line.
In short, the riders who chose the soft tires were taking a big gamble, and using the tires for conditions they were not designed to handle. Many riders – among them Marc Márquez and Maverick Viñales – had expected to come in and swap bikes at some point as the track dried. The soft tires were more than capable of handling half race distance on a drying track, being swapped for intermediates or slicks.
But the track didn't dry out enough to allow riding with slicks, or even intermediates. There were large sections of the circuit which remained fully wet, while others had a wide drying line. More experienced riders understood that the track would not dry out as quickly as it had at the Sachsenring, because of the nature of the circuit. "At the Sachsenring, it was possible to switch over to slicks because it dried so quickly," Eugene Laverty explained. "There's one line at that track, and it's just a case of joining the dots between the apexes. Here there are so many left to right corners and there's a lot of variation in the lines here between the different bikes so the track wouldn't dry as quick. It's one line in Germany but there's so many left to rights here that riders are going everywhere. "
