The premier class had a tricky start in Misano, FP1 starting dry but with the cloud cover becoming menacingly grey and ending in a downpour for the final dozen minutes of the session. Although the session was cut short and not many were tempted to go out on rain tyres, it was great timing for Maverick Viñales, the new Aprilia recruit impressively putting his name at the top of the timesheets just before the rain arrived, aided by a recent test in Misano. Joan Mir was one of the few men who did some laps on the soaking track and his dry track time was good enough for second, eight hundredths of a second slower than the Aprilia. Pecco Bagnaia was one of the early leaders of the session but got demoted to third after his bike refused to rejoin the action for the second half of the session and the rain arrived once he did rejoin. Teammate Jack Miller joined him in fourth, with Alex Rins rounding out the top five.
Fabio Quartararo got stuck in a Repsol Honda sandwich in FP1, in between Pol Espargaro in 6th place and wildcard Stefan Bradl in 8th, closely followed by Marc Marquez, the Spaniard also having a play on rain tyres. Aprilia bookended the top 10, with Aleix Espargaro dropping to 10th, four tenths of a second behind his teammate. Johann Zarco missed out on the top 10 despite being within half a second of the leader, while the reshuffled Yamaha line-up was still getting up to speed, with Franco Morbidelli returning from injury in 16th position and the novel sight of Andrea Dovizioso in turquoise down in final place while he got reacquainted with the Yamaha.