The last test of the preseason is something of a moment of truth for the MotoGP factories. From the tropical heat of Malaysia and Thailand, the paddock heads to the Arabian peninsula, and cool desert evenings of the Losail International Circuit in Qatar.
Air temperatures start in the mid 20s°C rather than the mid 30s°C, and drop into the high teens heading into the evening. That temperature difference means that air density is a couple of percent higher at Qatar. That in turn means more oxygen going into the engine, and better combustion efficiency.
Translating all that from vague engineering platitudes into real-world racing, colder air means more power all the way through the rev range. Engines run better, pick up more aggressively, and pull harder flat out in the cool Qatari evenings than in Sepang’s punishing tropical heat.
An engine that seemed docile in Sepang suddenly feels aggressive at Losail. An engine which was just about manageable in Thailand is a barely controllable beast in Qatar.
And with just two weeks to go before the start of the 2018 MotoGP season, it’s too late to fix the problem. Riders are left wrestling a wild bull for the rest of the year.