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500cc Supercharged Three-Cylinder -1940
One, two, three, four and even eight cylinders: Moto Guzzi tried everything, and this threecylinder bike was one of its best efforts. Yet the ban on superchargers after WWII brought its career - which was limited to a single race in 1940- to an end. The three-cylinder, which was a personal project of Carlo Guzzi, debuted in 1939, when most European factories were investigating supercharged multi-cylinders.
With nothing in common with the touring three-cylinder model of 1932, whose cylinders were virtually horizontal, this competition bike was one of the most innovative of all time and -like his first design of 1921 Â–demonstrated the immense creativity of Carlo Guzzi.
Breaking the Mold
It broke with all his normal concepts: The unitconstructed engine was as compact as it was light, thanks to the intensive use of magnesium and other special light alloys. A massive casing covered the chain driving the twin overheadcamshafts, while the capacious cover for the clutch was mounted on the end of the crankshaft (an unusual configuration for Guzzi). The Cozette vane-type supercharger and the carburetor were mounted above the gearbox, which - another original feature - had five speeds. The cycle part was also unorthodox: The engine, which contributed to frame rigidity, was hung from a single upper beam, and the swing arm rear suspension was controlled by a horizontal spring beneath the engine.
Engine: 492cc (56x60mm) air-cooled threecylinder four-stroke inclined at 45 degrees; sleeved light-alloy cylinder block and head; dry-sump lubrication
Power Rating: 80 hp @ 8000 rpm
Valves: twin chain-driven overhead-camshafts
Fuel System: Cozette supercharger and Dell'Orto carburetor
Transmission: 5-speed; dry multi-plate clutch; chain final drive
Suspension: Brampton girder forks (front); swing arm with horizontal spring beneath engine and lateral friction dampers (rear)
Brakes: magnesium drum (front & rear)
Wheels: 21 inch (front & rear)
Weight: 386 lb
Maximum Speed: 110 mph
Just one incomplete example of this superbike survives - in the Moto Guzzi museum.