Movistar Yamaha MotoGP's Italian rider Valentino Rossi rides his bike during the second day of 2017 MotoGP pre-season test at the Sepang International Circuit on January 31, 2017. / AFP / MOHD RASFAN
Kuala Lumpur: Suzuki's Andrea Iannone was the fastest rider on day two of the 2017 test season at Malaysia's Sepang circuit Tuesday while Jorge Lorenzo and Valentino Rossi leapt up the timesheets.
But the session was briefly red-flagged after Spaniard Tito Rabat crashed and was taken to hospital.
The Marc VDS Honda rider fractured his hand and sustained injuries to his left knee, right foot and wrists, and will not take any further part in the testing.
Iannone, logged 1min 59.452 seconds -- 00.406 seconds faster than Spaniard Maverick Vinales on a Yamaha.
Motorcycling superstar Rossi -- debuting Yamaha's new fairing with "internal" winglets following the ban on external ones this year -- registered 2min 00.254 seconds and was fourth fastest, an improvement from Monday's eighth spot.
"We tried a different frame, different chassis, different tyres and I finished in fourth and improved the lap time so it was a good day," said Rossi.
"The fairing was not a big difference but the new chassis was a good difference. Compared to the old one, we've still not decided, we need to continue working tomorrow."
The Italian superstar is targeting an elusive 10th world title in a new MotoGP season dominated by riders switching allegiances and thereby changing bikes too.
Three-time world champion Lorenzo on a Ducati was the eighth fastest at 2min 00.484 seconds, an improvement from his 17th standing on Monday.
"I'm really happy with the progress," Lorenzo said.
"Today I understand the bike a lot better and I can extract more performance from it, although I'm still a long way off my limits."
Damp conditions in the morning left riders pushing for faster timings in the afternoon.
Alvaro Bautista from the Pull and Bear Aspar Team was third fastest at 2 min 00.218 seconds while current world champion Marc Marquez on a Honda was tenth on the timesheets, logging 2min 00.531 seconds.
The third and final day of the test session in Sepang will begin Wednesday.
The second round of testing will be held on Phillip Island in Australia from February 15-17 and a third round in Qatar from March 10-12.
The 18-race MotoGP season gets under way in Qatar on March 26.