For reference, the lap record at Misano is a 1m30.390s set by Jorge Martin last year.
KTM wildcard Pol Espargaro now goes top with a 1m32.722s from Alex Rins and Vinales.
It's all change at the top as Maverick Vinales takes over on his Aprilia with a 1m33.563s.
After the first flurry of laps, KTM's Jack Miller leads the way with a 1m35.380s.
It's a hive of activity on track in the opening moments of this FP1 session as everyone has headed out.
FP1 begins!
The opening 45-minute practice of the Misano weekend has gone green at Misano.
There will be two wildcards on the grid this weekend at Misano.
Honda is fielding Stefan Bradl, while Pol Espargaro is back with KTM.
They will be carrying out vital preparation work for Monday's in-season test at the track.
15-minute warning
The first Moto2 session of the weekend has come to a close, which means there's just 15 minutes until MotoGP bikes are on track at Misano!
Marc Marquez comes to Misano as a grand prix winner for the first time since the 2021 Emilia Romagna GP.
The Gresini rider revealed on Thursday that he gathered his old Honda team and told them to share in the victory with him.
As far as this weekend is concerned, Marquez is looking to start with the same feeling on his Ducati he had in Austria last month.
One of the big talking points coming to Misano is the crash between Bagnaia and Alex Marquez at Aragon.
It led to a fiery outburst between the pair last week, though Bagnaia apologised on Thursday at Misano for accusing Marquez of deliberately causing the crash.
Read Bagnaia's statement here
Coming into this weekend's 13th round of the 2024 season, Jorge Martin leads the championship by 23 points from Francesco Bagnaia.
The Pramac rider, of course, dominated at Misano last year.
Mir sits out Friday
Honda's Joan Mir missed his Thursday media duties because he was ill. HRC has now confirmed he will sit out all of Friday's practice too.
Good morning and welcome to our live coverage of the 2024 MotoGP San Marino Grand Prix!
It's a lovely Friday at Misano and FP1 is due to get underway at 9:45am UK time.