Andrea Dovizioso led the way as Ducati dominated the first day of MotoGP testing at the Red Bull Ring, before next month's Austrian Grand Prix.
The two-day private test is largely intended for familiarisation ahead of the first race at the venue since it was reopened, having last hosted motorcycle grands prix in 1997.
The bulk of the field is in attendance, with only the factory Honda outfit and Tech3 Yamaha not participating, while Aprilia - running 2017 recruit Sam Lowes and Mike di Meglio - lapped without timing transponders.
Ducati riders filled the top four places, with Dovizioso the only rider to lap below the 1m24s barrier with a 1m23.764s set in the final 20 minutes.
Team-mate Andrea Iannone - who was fastest in the morning and until Dovizioso's late lap in the afternoon - was second, 0.583 seconds adrift, just ahead of Pramac satellite rider Scott Redding.
Testing with Ducati for the fourth time this year, two-time MotoGP champion Casey Stoner set the fourth-fastest time, 0.738s slower than Dovizioso.
Suzuki's Maverick Vinales was the best of the rest in fifth, 0.831s off the ultimate pace, followed by more Ducatis, from satellite riders Hector Barbera, Eugene Laverty, and Danilo Petrucci.
Beyond the seven Ducatis in the top eight, Yamaha pair Valentino Rossi and Jorge Lorenzo were ninth and 12th for the day, 1.290s and 1.411s slower than Dovizioso.
Jack Miller was the fastest Honda in 13th for Marc VDS, edging out LCR's Cal Crutchlow.
Ahead of its MotoGP entry in 2017 with Bradley Smith and Pol Espargaro, KTM tested alongside other teams for the first time with its RC16 prototype.
Mika Kallio was 13th in the morning and then 16th in the afternoon, 2.292s off the pace, with Moto2 rider Thomas Luthi 18th, the pair split by Miller's team-mate Tito Rabat.
1. Andrea Dovizioso (Ducati) 1m23.764s
2. Andrea Iannone (Ducati) 1m24.347s +0.583s
3. Scott Redding (Pramac Ducati) 1m24.461s +0.697s
4. Casey Stoner (Ducati) 1m24.502s +0.738s
5. Maverick Vinales (Suzuki) 1m24.595s +0.831s
6. Hector Barbera (Avintia Ducati) 1m24.649s +0.885s
7. Eugene Laverty (Aspar Ducati) 1m24.751s +0.987s
8. Danilo Petrucci (Pramac Ducati) 1m24.992s +1.228s
9. Valentino Rossi (Yamaha) 1m25.054s +1.290s
10. Aleix Espargaro (Suzuki) 1m25.099s 430s +1.245s
11. Yonny Hernandez (Aspar Ducati) 1m25.171s +1.407s
12. Jorge Lorenzo (Yamaha) 1m25.175s +1.411s
13. Jack Miller (Marc VDS Honda) 1m25.345s +1.581s
14. Cal Crutchlow (LCR Honda) 1m25.438s +1.674s
15. Loris Baz (Avintia Ducati) 1m25.994s +2.230s
16. Mika Kallio (KTM) 1m26.056s +2.292s
17. Tito Rabat (Marc VDS Honda) 1m26.195s +2.431s
18. Tom Luthi (KTM) 1m26.405s +2.641s