Petrucci leads second day of Sepang MotoGP test amid tyre drama

Towards the end of the first hour of the session, Baz was thrown from his Avintia Ducati along the start/finish straight at 180mph as his rear tyre failed.

The Frenchman miraculously emerged unscathed and was able to walk back to the pits.

"The rear tyre locked up when I was doing 290km/h," explained Baz. "At the last corner I felt something strange and I thought about completing the lap and coming in.

"At first I thought it could be the engine or the gearbox, but finally it looks like it was the tyre. I was very lucky."

While Michelin is uncertain exactly what caused the failure, the French firm's technical director Nicolas Goubert said it may have been related to tyre pressures.

"These bikes don't have a pressure sensor on the tyre, although what we do is recommend a minimum and maximum pressure," he said.

"It might be possible that what happened has something to do with it, although until we have the results of our test we won't know."

As a precaution, the soft Michelin tyre compound was withdrawn from use once the session was resumed after an hour-long investigation into what caused the failure.

Lorenzo on the pace

This resulted in Petrucci - who had set his best lap of 2m00.095s shortly before Baz's crash - remaining on top for the rest of the session, albeit just 0.060s clear of Day 1 pacesetter Jorge Lorenzo.

The factory Yamaha rider, recovering from an earlier crash at Turn 5, set his best time of 2m00.155s in the very closing moments of the session on the harder tyre, putting him less than two tenths ahead of Baz's Avintia teammate Hector Barbera.

Marc Marquez was fourth, 0.798s off the pace, on the best of the Repsol Hondas, with Cal Crutchlow making a late jump to fifth aboard the satellite LCR machine.

Valentino Rossi was another late improver, going sixth fastest ahead of the Ducatis of Andrea Iannone and Scott Redding - albeit some way off Lorenzo's pace for the second day in a row.

Casey Stoner finished his first competitive session since his retirement in ninth place aboard last year's Ducati GP15, just over a second off the pace with a time of 2m01.103s, a second up on his best effort from private testing on Saturday.

Tech 3 Yamaha's Bradley Smith completed the top 10, while Dani Pedrosa on the second Repsol Honda could do no more than 12th, 1.380s off the pace, behind Maverick Vinales on the best of the Suzukis.

Full testing times:

Pos	Rider	Team	Time	Gap	Laps
1	Danilo Petrucci	Octo Pramac Yakhnich	2:00.095		46
2	Jorge Lorenzo	Movistar Yamaha MotoGP	2:00.155	0.060	32
3	Hector Barbera	Avintia Racing	2:00.387	0.292	32
4	Marc Marquez	Repsol Honda Team	2:00.843	0.748	52
5	Cal Crutchlow	LCR Honda	2:00.899	0.804	55
6	Valentino Rossi	Movistar Yamaha MotoGP	2:01.021	0.926	54
7	Scott Redding	Octo Pramac Yakhnich	2:01.049	0.954	42
8	Andrea Iannone	Ducati Team	2:01.052	0.957	39
9	Casey Stoner	Ducati Team	2:01.103	1.008	45
10	Bradley Smith	Monster Yamaha Tech 3	2:01.107	1.012	59
11	Maverick Vinales	Team SUZUKI ECSTAR	2:01.421	1.326	59
12	Dani Pedrosa	Repsol Honda Team	2:01.475	1.380	36
13	Yonny Hernandez	Aspar MotoGP Team	2:01.644	1.549	41
14	Andrea Dovizioso	Ducati Team	2:01.723	1.628	35
15	Pol Espargaro	Monster Yamaha Tech 3	2:01.992	1.897	32
16	Aleix Espargaro	Team SUZUKI ECSTAR	2:02.092	1.997	39
17	Tito Rabat	EG 0.0 Marc VDS	2:02.328	2.233	54
18	Stefan Bradl	Aprilia Racing Team Gresini	2:02.372	2.277	45
19	Loris Baz	Avintia Racing	2:02.611	2.516	26
20	Katsuyuki Nakasuga	Yamaha Test Team	2:02.691	2.596	43
21	Alvaro Bautista	Aprilia Racing Team Gresini	2:02.876	2.781	52