Motorcycle.com

The Repsol Honda rider requested the switch to the pneumatic valve from the conventional spring valve engine and, after recording impressive lap times in the British Grand prix practice sessions on June 20, received the go-ahead to use the new engine for the race. Teammate Dani Pedrosa will continue to use the conventional spring valve engine that has powered him to second in the rider standings.

The data collected from the Donington race will be vital in preparing Haydens RC212V in Assen, The Netherlands on June 28 for the Dutch TT.

Im feeling pretty positive going into Assen, says Hayden. We learned a lot about the new engine last weekend fuel consumption, tyre life and so on that we hope we will be able to put to good use at Assen.

Pneumatic valve technology uses air pressure to control the opening and closing of the valves. In conventional spring valve engines, open valves compress coils which then expand to close the valves. But as MotoGP engines reach levels 18,000 rpm and higher, the physical strain on the springs also increases, raising the risk of a mechanical failure.

First introduced by Renault in Formula 1 racing in the mid-1980s, pneumatic valve engines provided better performance at higher rpm levels. With this technology, Renault engines won six constructor titles in the 90s.

Converting a motorcycle to use pneumatic valves requires more than just plugging in a new power plant as pneumatic valves systems are also smaller and lighter than conventional spring valves. Other bike adjustments are required to make up for the change in weight distribution and shift in the center of gravity.

Pneumatic valve engines were first used in MotoGP racing in 2002 with the Aprilia RS3. Suzuki and Kawasaki switched to pneumatic valve systems in 2007. Yamahas satellite team Tech 3 made the switch as well. Honda first debuted its pneumatic valve engine at the June 1 race in Mugello, Italy with grand prix veteran Tadayuki coming out of retirement to race as a wildcard entry.

Ducati, meanwhile, uses its own proprietary cam-based desmodromic system which has proven successful in MotoGP and World Superbike racing, including Casey Stoners MotoGP 2007 championship.