Following Sunday's Valentino MotoGP season finale, riders returned to the circuit on Tuesday for the start of an official winter test.
The two-day outing marks the first chance for riders to appear with their 2017 teams.
Tuesday's debuts included triple MotoGP champion Jorge Lorenzo at Ducati, Maverick Vinales at Yamaha, Andrea Iannone at Suzuki, Bradley Smith and Pol Espargaro at KTM, Aleix Espargaro at Aprilia, plus Alvaro Bautista and Karel Abraham at Aspar.
The four rookies stepping up to MotoGP from Moto2 were also on track: Johann Zarco and Jonas Folger at Tech 3 Yamaha, Alex Rins at Suzuki and Sam Lowes at Aprilia. Only Lowes has previously tested for his team.
Former Aspar racer Eugene Laverty made his debut on an Aprilia RS-GP, which he will help develop alongside his 2017 World Superbike commitments. Francesco Bagnaia got to ride an Aspar Ducati as a reward for taking two victories for the team's Moto3 project.
Danilo Petrucci has returned to Italy for family reasons and is being replaced at Pramac by Ducati test rider Michele Pirro.
Vinales took over from new team-mate Rossi at the top of the timesheets in the middle of the afternoon. Vinales used the 2016 Yamaha today, while Rossi also tried the 2017 bike.
Rossi, Pol Espargaro, Cal Crutchlow, Iannone, Tsuda, Lowes and Laverty all walked away from falls.
Reigning champion Marc Marquez was on track with both the 2016 and 2017 versions of the Honda RC213V. The Spaniard led the early stages, before the Yamahas hit the front. As rumoured, the new Honda sounds like it has a 'big bang'-style engine.
Lorenzo made a late push up the timesheets for a close third on the Ducati, having spent all day on the 2016 machine. Team-mate Andrea Dovizioso did however spend time on the GP17.
Testing, which took place from 10am to 5pm, continues on Wednesday...
1. Viñales, Maverick
SPA Movistar Yamaha MotoGP (YZR-M1) 1m 30.930s
2. Rossi, Valentino
ITA Movistar Yamaha MotoGP (YZR-M1) 1m 30.950s +0.020s
3. Lorenzo, Jorge
SPA Ducati Team (Desmosedici GP16) 1m 31.052s +0.122s
4. Marquez, Marc
SPA Repsol Honda Team (RC213V) 1m 31.102s +0.172s
5. Dovizioso, Andrea
ITA Ducati Team (Desmosedici GP16/17) 1m 31.131s +0.201s
6. Crutchlow, Cal
GBR LCR Honda (RC213V) 1m 31.156s +0.226s
7. Iannone, Andrea
ITA Team Suzuki Ecstar (GSX-RR) 1m 31.165s +0.235s
8. Redding, Scott
GBR Octo Pramac Yakhnich (Desmosedici GP15/16) 1m 31.242s +0.312s
9. Barbera, Hector
SPA Avintia Racing (Desmosedici GP14.2/16) 1m 31.286s +0.356s
10. Pedrosa, Dani
SPA Repsol Honda Team (RC213V) 1m 31.306s +0.376s
11. Miller, Jack
AUS Estrella Galica 0,0 Marc VDS (RC213V) 1m 31.477s +0.547s
12. Bautista, Alvaro
SPA Aspar Ducati (Desmosedici GP16) 1m 31.674s +0.744s
13. Pirro, Michele
ITA Octo Pramac Yakhnich (Desmosedici GP16/17) 1m 32.068s +1.138s
14. Espargaro, Aleix
SPA Factory Aprilia Gresini (RS-GP) 1m 32.177s +1.247s
15. Baz, Loris
FRA Avintia Racing (Desmosedici GP15) 1m 32.315s +1.385s
16. Folger, Jonas
GER Monster Yamaha Tech 3 (YZR-M1) 1m 32.450s +1.520s
17. Zarco, Johann
FRA Monster Yamaha Tech 3 (YZR-M1) 1m 32.462s +1.532s
18. Rabat, Tito
GBR Estrella Galica 0,0 Marc VDS (RC213V) 1m 32.578s +1.648s
19. Espargaro, Pol
SPA KTM MotoGP Factory Racing (RC16) 1m 32.613s +1.683s
20. Smith, Bradley
GBR KTM MotoGP Factory Racing (RC16) 1m 32.806s +1.876s
21. Rins, Alex
SPA Team Suzuki Ecstar (GSX-RR) 1m 32.811s +1.881s
22. Laverty, Eugene
IRL Aprilia Test Rider (RS-GP) 1m 32.935s +2.005s
23. Abraham, Karel
CZE Aspar Ducati (Desmosedici GP14.2/15) 1m 33.231s +2.301s
24. Lowes, Sam
GBR Factory Aprilia Gresini (RS-GP) 1m 33.359s +2.429s
25. Tsuda, Takuya
JPN Suzuki Test Rider (GSX-RR) 1m 34.110s +3.180s
26. Bagnaia, Francesco
ITA Aspar Ducati (Desmosedici GP14.2) 1m 36.940s +6.010s
Blue Name = No Concessions.
7 engine changes for the season. Engines must be identical throughout season within same team (development freeze). 5 days of private testing.
Black Name = Concessions.
9 engine changes. No engine development freeze. Unlimited private testing.
Live Updates: Follow @Crash_MotoGP
Official Valencia MotoGP records:
SPA Yamaha 1m 29.401s
Fastest race lap:
SPA Yamaha 1m 31.171s
2016 Valencia MotoGP: fastest race laps
1 Lorenzo 1m 31.171s
2 Iannone 1m 31.196s
3 Rossi 1m 31.276s
4 Marquez 1m 31.299s
5 Viñales 1m 31.313s
6 Dovizioso 1m 31.317s
7 P. Espargaro 1m 31.744s
8 Pedrosa 1m 31.811s
9 A. Espargaro 1m 31.867s
10 Crutchlow 1m 31.912s
11 Smith 1m 32.050s
12 Barbera 1m 32.334s
13 Bautista 1m 32.387s
14 Petrucci 1m 32.452s
15 Redding 1m 32.577s
16 Laverty 1m 32.659s
17 Miller 1m 32.811s
18 Bradl 1m 32.875s
19 Baz 1m 32.938s
20 Rabat 1m 33.030s
21 Hernandez 1m 33.188s
22 Kallio 1m 33.208s
By Peter McLaren