The countdown to the opening round of the 2013 MotoGP World Championship gets underway later this weekend when pre-season testing at Sepang begins with a special two-day outing for a handful of CRT teams.

As has become tradition, the Malaysian circuit heralds the start of a new year with the first official test of the season.

But while most eyes will be trained on the start of the main test on 5th February - which should mark Valentino Rossi's first dry laps since his Yamaha return, the Ducati debut of Ben Spies and a chance for rookies Marc Marquez, Bradley Smith and Andrea Iannone to measure themselves against the full 2013 line-up - some of the CRT class will get a head-start with a special test beforehand.

Open to the CRT teams that will be using the much-discussed Magnetti Marelli ECU in 2013 - a year before it becomes compulsory to all MotoGP teams -, those participating in the test should be Avintia's Hector Barbera and Hiroshi Aoyama (fitness permitting, CAME Ioda's Danilo Petrucci and Lukas Pesek, and NGM Forward Racing's Colin Edwards and Claudio Corti.

Michael Laverty's PBM-designed chassis is also expected to use the standard ECU in 2013, but as the bike won't be ready to ride for this test, he will instead be out on team-mate Yonny Hernandez's spare ART machine.

Other riders not expected to use the ECU are Aspar's Aleix Espargaro and Randy de Puniet, Cardion AB's Karel Abraham and Gresini's Bryan Staring. They will join the main test on February 5th.

CRT ECU testing takes place on 3-4 February, while the main test - also open to those using the standard ECU - will run from 5-7 February.

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