MotoGP: Pneumatic valve Honda makes debut

HONDA'S pneumatic-valve-spring engine made its long-awaited appearance at Mugello – and with several more units already being air freighted from Japan, the factory riders could be racing it as soon as Catalunya next week.

The surprise appearance fielded former GP racer and four-times winner Tadayuki Okada (41). It was the Honda factory tester’s first GP since 2000, although he has raced in the Suzuka 8-hour and Japanese Superbike races in the interim.

Team manager Kazuhiko Yamane and large project leader Shinichi Kokubu gave a briefing to outline progress on the motor, which means that the usual technical leaders Honda will finally catch up with Yamaha, Suzuki and Kawasaki in using pneumatic valve springs.

They were ready to use the engine at the next race, said Yamane, depending on results at Mugello.

The aim was improved acceleration and top speed, and the latter at least had been achieved, with some 1,000 rpm added to the top of the rev range; but there was still some difficulty with mid-range response, revealed Okada later.

Testing had started in November last year, of a motor whose chief advantages are higher revs and less internal friction.

The motor was completely different from the interim valve-spring model currently used by the factory riders, although it shared the same engine mounting points and was thus interchangeable in the chassis, said Kokubu.

Technical details were sparse, such figures as bore-and-stroke, rev ceiling and horsepower being kept secret; but Kokubu did reveal that the mechanics of the system “are very similar to our F1 engine”.

Okada has been testing the bike at Motegi and Suzuka, as well as at the Honda Tochigi proving ground. Why had HRC gone ahead with this wild card entry for Okada? “We wanted to get development data at a grand prix circuit, to study and verify the performance,” said Kokubu.

The difficulty was to reconcile the conflicting demands of racing. “Fuel consumption is very important,” he explained. The reduced engine friction was a help, but on the other hand the increased rev ceiling worked against it. “We are working on improving combustion efficiency, both electronically and mechanically,” he said.