Ducati had always built single-cylinder machines with engines designed by Dr. Fabio Taglioni after he left FB Mondial in 1954. Taglioni brought with him a new idea for a simple, shaft-and-bevel single-cylinder engine with a unit-construction crankcase that could be scaled up from its initial 100cc design as the Ducati Gran Sport racer. It would also gain a DOHC cylinder head, as used in Ducati’s early F3 racers, or even with his legendary desmodromic-valve operation system, which later became synonymous with Ducati performance.
While Ducati used the desmo system on its racing machinery from the 1950s onwards, it never offered a road bike with a desmo cylinder head until 1968. Taglioni tried out the desmo head on racing singles based on a new crankcase in 1967, the first “widecase” models, and after taking top-10 spots in the 350cc and 500cc races at Modena that year, the factory offered its first desmo roadster at the Cologne show that September. Surprisingly, they were first offered on street scrambler (SCR) models, and in 1968, the Mark 3D was the first proper desmo-head factory café racer in 250cc and 350cc capacities that featured a chromed, jelly-mold steel tank, clip-on handlebars, flanged alloy rims and a tachometer as standard.
The 450cc model came in 1970, initially in the Mark 3 guise, although it was later available in the Shotgun Silver paint scheme with fiberglass racing bodywork, and later still, in the miniature 750 Sport bodywork in orange and black with a disc brake as standard. The 450 Desmo could be tuned to 50 HP at 9,000 RPM, and clever racers used twin-plug ignition, big valves and 42mm Dellorto carbs with a 10:1 compression ratio. This gave the 450 Manx Norton power in a far lighter package, and as racing machines, the desmos were simply fantastic. This compelling 1971 Ducati 450 Desmo racer sold new in Sweden in 1971. It has a limited racing history and changed owners twice before the MC Collection bought it in 2013. The first owner was an aircraft mechanic, who kept the bike updated until it was sold in the mid-1990s to Sven Erik Johansson of Långshyttan, Sweden.
Report by mecum.com