After a delayed debut with the #1 plate on his Repsol Honda, Casey Stoner put his new RC213V on top of the timesheets during day two of the Sepang MotoGP test.
The double world champion had been forced to miss the entire opening day of 2012 testing following a back strain, while stretching in the pits yesterday morning.
“It happens two or three times a year to me, but normally not around bikes and yesterday was far beyond anything I've ever had before,” explained Stoner. “I've had two or three scans on my back because of the [125cc] crash I had in 2003. I've had back problems ever since then, but the scans have never shown anything conclusive.
“We'll have another scan. I've still got to have a scan on my neck, from Assen last year. I haven't got full movement. So I have to get both of them checked out. It's quite frustrating, but it's just something that happens. It seems you have a good back or bad back. At least it doesn't affect me most of the time.”
Stoner used 'off the shelf' pain killing tablets to "take the edge off" the back problem on Wednesday and was able to ride for 29 laps, although the morning began worryingly when he tweaked another part of his back.
“I could still ride well, just not do as many laps as I'd like,” said Stoner.
The loss of the opening day also meant Stoner couldn't waste any time in getting up to speed, but still enjoyed riding a grand prix prototype for the first time since November's Valencia test.
“Your mind is one or two corners behind at first, but it was good to get back out on track and feel the wind in your face again,” he said.
Stoner's best lap - his 19th - was a 2min 0.895sec.
After a false 1min 58sec time for Ben Spies had been corrected, Stoner finished the day 0.157sec ahead of the Texan, whose factory Yamaha team-mate Jorge Lorenzo - quickest on day one - was just 0.173sec behind in third.
“When I first saw Spies' [false] time I thought 'freak'! Then I looked again and thought 'hang on - 2.7sec quicker?' He should have gone a little slower and done a high 1m 59s!” joked Stoner.