Ducati Desmosedici is the name of the series of 4-Stroke V4 Prototype Motorcycles developed by Ducati to compete in the MotoGP World Championship. GPx indicates the version of the bike, where x corresponds to the year the bike raced (ie the Desmosedici GP8 raced in 2008). Ducati also made a Desmosedici racing replica called Desmosedici RR
Ducati history is classically based on L-twin engines, using desmodromic valve technology. Initially, Ducati considered the possibility of creating a MotoGP ‘super-twin’, taking advantage of the MotoGP regulations that give twin-cylinder machines a considerable weight reduction over four, five or six-cylinder bikes. However, analysis indicated that a twin-cylinder engine would not have been able to produce the required amount of power (more than 230 hp), without excessively increasing the number of revs. A Twin would have had to rev at over 17,000 rpm, but this would require a very short stroke and a very large bore, as a result producing possible combustion problems.
The basis of the design of the Desmosedici engine therefore is two classical Ducati L-Twins next to each other, making a Double L Twin with 2 cylinder Stroking at the same time (also called Twin Pulse). With four valves per cylinder, the total number of valves is sixteen - Desmosedici means desmodromic distribution with sixteen valves shortened in Italian
Design had started in 2001 with Alan Jenkins, the bike was unveiled at the 2002 Italian GP at Mugello, for use in the following seasons MotoGP World Championship. Vittoriano Guareschi, the Ducati Corse test-rider, followed every phase of the Desmosedici’s development process from early testing to track debut and the project’s evolution. In 2007, Ducati's pilot Casey Stoner, riding a Desmosedici, obtained Ducati's first MotoGP World Championship Title.
At 989 cc, the GP4's top speed record of was set by Loris Capirossi on at IRTA Tests in Catalunya, Spain.
The new rider with Capirossi was Spanish rider Sete Gibernau. After encouraging winter tests, the Desmosedici GP6 took its first win of 2006 in the opening GP at Jerez de la Frontera, Spain, followed by a podium in Qatar. Capirossi led the championship for a short while, but at the start of the Grand prix de Catalunya at Barcelona, Gibernau's bike collided with Capirossi's after Gibernau braked too late and compressed his brake lever ferther after impacting it on the back of Capirossi's bike. Both riders ended up injured and in the hospital, with Gibernau sustaining a broken collar bone, and both missed the Dutch Grand Prix at Assen. Capirossi returned at the British Grand Prix, while Gibernau was replaced by German Alex Hofmann for the Dutch Grand Prix, the British Grand Prix, and also the Czech Grand Prix after undergoing additional surgery. With Gibernau still sidelined for the final round of the season at Valencia, Ducati recalled Bayliss, who was recently crowned World Superbike champion. The race was won by Bayliss, his first MotoGP victory, with Capirossi taking second place for the first Ducati 1-2 finish.
Ducati started its project to build an 800 cc MotoGP bike extremely early and according to Ducati's racing chief Filippo Preziosi, by August 2006 Ducati had already built 20 800 cc engines with various specifications. In addition, an early version of the bike was track tested for the first time during early May 2006. Public testing with the bike began at the Brno Track, where Loris Capirossi had won the day before riding the GP6, on the 21st of August. Capirossi's lap times on the prototype GP7 were only 1.4 seconds off his track record time set on the 990 cc GP6.
Further testing of the GP7 in Motegi, Japan, revealed that the 800 cc machine could run faster laps than the higher-displacement 990 cc bikes, and held nearly a second advantage over the next fastest 800 cc bike, a Honda ridden by Dani Pedrosa.
It was noted in Motosprint that as of the Le Mans Grand Prix the GP7 had a advantage over Honda and Yamaha MotoGP bikes. This horsepower advantage gave it a significant speed advantage through the early part of the season. The bike was rumored to have aerodynamic settings that could be changed to increase top speed if needed.
MotoGP's 800 cc era officially began with the first race of the 2007 MotoGP season, at the Losail International Circuit in Qatar. Casey Stoner won the race on the new GP7. The bike had a clear top speed advantage over the rest of the grid, due to its higher output motor. A new track record was set on the GP7. Second place contender and five time former World champion, Yamaha's Valentino Rossi, testified that "unfortunately, there was too much difference between (our) bikes in the straight" and "Our Yamaha will never go as quick on a straight as the Ducati." These words turned out to be true, as the GP7 enjoyed a top speed advantage throughout the season, although the other manufacturers (Yamaha, Honda, Kawasaki and Suzuki) closed the gap significantly by the end of the year. Stoner and his Bridgestone-shod Ducati proved to be the top combination in MotoGP and he won the world championship at Motegi, Japan, on September 23 2007, four races before the end of the season.
At the end of season, Ducati's chief engineer Alan Jenkins was awarded the Sir Jackie Stewart Award for brilliance throughout the season.
For purposes of avoiding chatter which was encountered on some occasions with GP7, the rigidity of the GP8's frame was altered, although further details of relevant modifications are not disclosed. In addition, in an attempt to reduce an effect described as "pumping", some modifications to the bike's suspension geometry were made.
As with its predecessor the GP8 contains a 4-cylinder 800cc engine with desmodromic actuation of its 16 valves. The engine has improved mid-range response and top-end power compared to that of the GP7.
During 2007 Ducati tested a special fuel saving clutch arrangement which disengaged the clutch during braking and reduced fuel consumption, however the arrangement was not incorporated in the GP8 as various advanced lubricants and fuels used with the GP8 are believed to provide comparable fuel savings, while decreasing internal engine friction and increasing maximum power.
In race trim the bike recorded an official top speed of at the 2008 Chinese motorcycle Grand Prix. However, in a video of the same race, Casey Stoner is seen to ride the bike at the speed of .
A distinctive feature of GP9 is its carbon fibre chassis, representing a departure from Ducati's traditional steel trellis chassis. Although carbon fibre chassis were tried in mid 1980s, currently no other MotoGP racing team uses them.
|Ducati Desmosedici GP8 (2008) Specifications|
|Engine type:||Liquid-cooled, 90-degree, V4 4-stroke with 16-valve, Desmodromic DOHC|
|Fuel System:||Fuel injection|
|Lubrication system:||Shell Racing V-Power|
|Maximum power:||Approximately (170 kW) 230 bhp|
|Maximum speed:||Approximately 350 km/h (in excess of 215 mp/h)|
|Type:||6-speed cassette-type gearbox, with alternative gear ratios available|
|Clutch:||Dry multi-plate slipper clutch|
|Chassis and running gear|
|Frame type:||Tubular steel trellis-style chassis, pressed aluminium swing-arm|
|Front suspension:||Ohlins upside-down 42mm front forks|
|Rear suspension:||Ohlins rear shock absorber, adjuster for pre-load, compression and rebound damping|
|Front/rear wheels:||16.5" front and rear|
|Front brake:||Brembo, two 320mm carbon front discs with four-piston callipers|
|Rear Brake:||Brembo, single stainless steel rear disc with two-piston callipers|
|Weight:||148 kg or 326 lb|
|Fuel capacity:||21 litres or 5.5 gallons|
In 2004, Ducati announced that they would be producing a low volume bespoke replica of the Desmosedici, available from 2006.
Termed the Desmosedici RR (Racing Replica), it was claimed to be the first true road replica of a MotoGP racing bike. Priority for ordering was given to Ducati 999R owners, with production projected at one bike per day at a retail cost of and . The price includes a three year warranty and servicing, cover plus a racing kit including a "race only" exhaust system, a "slip-on" muffler and complimentary fuel and ignition mapping in a "race ECU". Production has been limited to 1500 motorcycles.
The bike was eventually launched at the 2006 Italian MotoGP event at Mugello, with production beginning in December 2007 and the first customer orders delivered from January 2008. Ducati guaranteed customer orders will be fulfilled by the end of 2008. The entire allocation for the United States sold out in five hours.
Ducati: back on track by developing innovative products; Although the Italian bike maker was given up for dead by some, new track-inspired designs and innovative engineering has put the company securely back on track.(The INDUSTRY)
Nov 01, 2006; Mugello, Valencia, Imola, Le Mans, Laguna Seca--mention these locales to any motorcycle aficionado and you're likely to see tears...