Here's the official press release from the Marlboro Ducati team on Rossi's outing on the GP12:
VALENTINO ROSSI RIDES THE DUCATI GP12 FOR THE FIRST TIME, AT JEREZ
Valentino Rossi took his first laps aboard the Ducati GP12 Friday morning on the Andalusian circuit in Jerez de la Frontera on a day that was sunny and warm (29° air, 41° track; 84° and 106° Fahrenheit, respectively), with the only imperfection being a strong wind. The Italian took to the circuit a few minutes after 11:00 and did a first run of six laps. With that outing having been completed with no problems, the work continued apace for the entire day, by the end of which Valentino had turned 50 laps.
Vittoriano Guareschi, who had worn his riding leathers on Thursday, today looked after Valentino's test, participating together with Filippo Preziosi in all of the mini-briefings between the various runs. Meanwhile, Franco Battaini carried out a test of the GP11, working with the electronics and chassis settings.
"I'm happy," Valentino Rossi said after the test. "I like the GP12. In my opinion, it's more enjoyable, more fun to ride. It was the first time we had it on the track, so we had some work to do, but the engine is nicer. It's a lot of fun, and you can do some nice slides. It's the bike we'll ride next year, so it was very important—and also very nice—to be among the first to take it on the track."
"We chose to have our factory riders—today Vale, tomorrow Nicky—try the bike beginning with its first test, because we think their feedback is essential for starting us on the right path for the early development," Filippo Preziosi said. "To be able to work with Vale for a full day is more than any technician could ask. We gathered considerable feedback that we'll translate into further design and development for next year's bike. The positive thing is that the technical choices made for the GP12 in the initial planning phase, in 2010—and I'm referring primarily to the engine, which is still a big-bang, and to the rear end—were endorsed by Valentino. This gives us great satisfaction, and we're optimistic about the work that still remains to be done. We know that our competitors are also working hard and developing their 2012 bikes, but that just makes the challenge better."