The Power Electronics Aspar Team and its new ART (Aprilia) CRT motorcycles took to the track for the first time since late January, as the private Jerez MotoGP test got underway on Monday.

MotoGP podium finisher de Puniet was unsurprisingly fastest of the handful of riders present, but was disappointed that his 1min 41.6sec lap time was slightly slower than he had managed at November's Jerez test - using an early version of the ART bike.

The official MotoGP Jerez race lap record is a 1min 39.731sec, set by Honda's Dani Pedrosa in 2010.

"Today we have tried many things, working mainly on the suspension and the electronics," explained de Puniet. "I'm a little upset because I have not lapped as fast as in November. But the bike is new and we have to get used to it.

"On one hand I would have liked to lap faster, on the other I am calm because we still have two full days to work. Now we will analyze the information from this first day of testing to see how we can improve for tomorrow. "

Team-mate Espargaro, returning to MotoGP this year after a season in Moto2, was over one-second slower than de Puniet as he battled fever and flu-like symptoms.

"As the day went on I felt terrible and I had a hard time staying focused," he confessed. "We were able to modify some aspects of the chassis, but decided to end the day early and rest for tomorrow."

As well as de Puniet and Espargaro, fellow ART teams Speed Master (Mattia Pasini) and PBM (James Ellison) are also present at Jerez.

PBM are due to make their track debut on Tuesday, but another Claiming Rule Team - Ioda Racing - completed its first test laps on Monday with race rider Danilo Petrucci.

Ioda is also using Aprilia RSV4 power, but with its own tubular steel chassis, of the kind seen on the early Ducati MotoGP bikes.

Young Italian Petrucci, yet to make a grand prix start, was happy with his machine, writing on his Twitter page (@Petrux9):

"Job done for today. We started working with our chassis since 3 o'clock and the feeling was better, immediately 1 second faster [than when using an Aprilia chassis]

"We don't have carbon brake and we have a superstock engine, 20 hp less than ART CRT. We are happy because is the first half day of working.

"The other CRT went a little bit faster after the checkered flag when was time to declare lap times, but the races are not today and tomorrow."

The official MotoGP website reports that Petrucci set a best lap time of 1m 43.3s, the same as Pasini.

The Ducati Test Team are also present this week. Test rider Franco Battaini was on track during day one, working on parts for the next official MotoGP test at Sepang.

Satellite MotoGP race riders Karel Abraham (Cardion AB) and Hector Barbera (Pramac) are due to be attending on days two and three respectively.

That will provide the first direct comparison between the pace of the Aprilia CRT machine and an official manufacturer MotoGP bike.