On a day when Honda officially confirmed that its pneumatic-valve engine will not be ready for the opening rounds of the 2008 MotoGP season, Nicky Hayden provided the factory with a welcome boast by taking last season's spring-valve design to the top of the Saturday timesheets, with a qualifying tyre, at the official Jerez test.

'Both riders are using 2008 RC212V engines with conventional valve actuation and will commence the 2008 World Championship with these engines,' Repsol Honda confirmed. 'The 2008 RC212V pneumatic-valve engine is under development at HRC, where engineers are focusing on improving power delivery, and will be raced by Hayden and Pedrosa when it is ready.'

Although the 2008 chassis was designed specifically for the pneumatic-valve engine, fears over the performance of the new powerplant saw the old engine placed inside the new frame from the opening test of this year - and it is that combination which has been receiving ever more track time since.

Hayden has almost single-handedly developed the two different versions, due to team-mate Dani Pedrosa's hand injury on the very first day of 2008 testing at Sepang, and the American had always hoped to race the pneumatic-valve engine - despite its problems - at the Qatar season-opener on March 9.

Nicky appeared to be pinning his hopes on a late breakthrough back at the HRC factory, but time has now run out for the new engine to be used at Qatar.

Nevertheless, at least he and Pedrosa can now concentrate all their attention on the valve-spring machine - which Hayden once again proved is as good as anything on qualifying tyres although, as so often this winter, he still needs to find more speed in race specification.

The announcement means that Repsol Honda will be the only factory team using a spring-valve engine at the start of the 2008 MotoGP season. Yamaha, Kawasaki and Suzuki have already switched to pneumatic valves, while Ducati uses its Desmodromic design.