- Dani Pedrosa sets the fastest time in practice for Aragon Grand Prix
- Friday's second practice session cancelled due to power cut
- Jorge Lorenzo was second fastest, with Casey Stoner in third
Dani Pedrosa set the fastest time in the opening practice session ahead of Sunday's MotoGP race in Spain, before a power cut short Friday's action.
Honda's Pedrosa recorded a lap of one minute 50.281 seconds around the Aragon circuit, but electrical problems prevented riders taking to the track for the day's second session.
As a result of the difficulties, Saturday's free practice will now be longer in order to help teams prepare for Sunday's grand prix -- the 14th round of the 2011 season.
Jorge Lorenzo, the Yamaha rider currently second in the world championship, was nearly half a second behind Pedrosa, with current standings leader Casey Stoner third fastest on board a Honda.
Pedrosa had his start to the season disrupted after a shoulder injury picked up at the 2010 Japanese Grand Prix forced him undergo surgery in April.
But the Spaniard has been in impressive form of late, finishing second in the last two races to rise up to fourth position in the world championship standings.
Australia's Stoner currently holds a 35-point lead over Lorenzo, the 2010 riders' champion, with only five rounds left of the season.
Italian Marco Simoncelli was fourth fastest around the track near the Spanish town of Alcaniz, with his compatriot Andrea Dovizioso fifth.
Aragon made its debut as a world championship venue in 2010, as a replacement for the Hungarian Grand Prix.