Ducati has already built an incredible 20 engines in preparation for next year's new 800cc formula in
MotoGP racing chief Filippo Preziosi has revealed.
Twenty engineers are working on the project in five teams, including the areas of engine design, electronics and what he called "the vehicle".
Preziosi spoke about the V4 when Loris Capirossi rode the bike for the first time during tests at the Brno circuit following Sunday's
Czech Republic[/color][/color][/color] MotoGP round, which he won on the current 990cc Ducati.
Ducati became the first factory to publicly unveil an 800cc MotoGP design on Monday, after previous tests held in private, shortly before
Valentino Rossitook to the track on Yamaha's prototype 800. Ducati's advanced state of preparation became evident as Preziosi talked enthusiastically about the machine.
"We started the project 15 months ago," he said. "The engine was on the dyno six months ago. We have built 20 engines, all to different specifications."
All share the V4 platform, and Ducati's trademark desmodromic valve-gear - unique in
motorcycle racing - which is apparently providing great benefits with the higher rpm of the smaller engine.
"We have a big knowledge of the desmodromic system, and it really helps us," Preziosi said. "It gives us good performance and consumption. When you are at low and medium rpm the system absorbs a lot less power than a valve spring, so the
fuel consumption is low and you can use the fuel better."
In some conditions the desmodromic system absorbs 30 to 40 percent less friction than a valve-spring engine. With a valve-spring engine if you want to run at 18,000rpm you need a very strong spring. But at four to eight thousand rpm you still have the same spring, even though you don't need it. With the desmo system you have no spring so the rockers operate with the right force at all revs, with never more than you need.
Preziosi declined to forecast the 800's rev ceiling compared to the 17,000rpm limit of the 990. "We have to increase this, but we don't by how much, because it will be a compromise between performance, power and driveability," he said.
He suggested the bike's top speed would be only 10-12kph less than the 990, which seems surprisingly optimistic considering its 20 percent reduction in capacity, but the 800 should benefit aerodynamically from a smaller frontal area.
By the end of his first day on the 800, Capirossi had lapped just 1.4secs slower than his fastest lap in Sunday's Czech Republic Grand Prix - but will not conduct further tests of the 800 before the end of the season in order to concentrate on the existing championship.
source crash.net
Re : Essais probable Ducati 800cc à Brno lundi 21/08 -
25/08/2006, 13h25
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