Gilera 500 1955

Gilera 500 Story

In 1946 the Gilera company modified its old Grand Prix racer, eliminating the supercharger and mounting two classic carburetors. This was a purely palliative change and the results were rather disappointing. At the same time the racing department of the company was already working on a new four-cylinder model designed to compete with the British single-cylinder motorcycles. The British had an advantage at the time, because they had been refining nonsuper-charged motorcycles since the 1930s and now were in a position to dominate the most important international races.

The new Gilera motorcycle was ready in 1948. The engine still had four cylinders but the forward inclina-
tion was barely 30°. Its cooling system used air rather than water, and one carburetor fed two cylinders. Another difference was in lubrication. The oil tank was no longer separate but occupied a lower chamber of the engine block.
The chassis of the four-cylinder was still mixed, with tubular elements and stamped-plate parts. There were rear friction shock absorbers and a front parallelogram fork. The total weight of the vehicle was reduced to only about 290 pounds.
But this new creation of Gilera did not become an immediate success. Although it won regularly in Italian races, even up against the fine Guzzi two-cylinder, it was not consistently successful against the British competition, especially the AJS 500 Porcupine two-cylinder and the Norton Manx, with its single-cylinder engine derived from the famous 1936 International M 30.

By 1950 the Gilera four-cylinder had been brought to the peak of its racing capacity. At the close of the 1949 season, the Gileras turned in a dazzling performance at Monza. Nello Pagani and Arciso Artesiani rode the four-cylinders to win first and second place. As the Gilera star rose, the fortunes of Geoffrey Duke and Leslie Graham, racers of Norton and the 1949 AJS world champion, began to decline. Gilera did not win the championship in 1950. Nevertheless Gilera had the best all-round Vi-liter at the time, and Umberto Masetti won the racer's championship with it.
In 1951 the British champion Duke

won the title for Norton, but the credit was chiefly the racer's rather than the motorcycle's.
The following year brought important changes. More horsepower was added to the engine, along with four simultaneous carburetors, and the chassis and the aerodynamics were also improved. That year Gilera and Masetti both won their championship titles.

At the beginning of the 1953 season, Geoffrey Duke switched to Gilera. The British press called him a traitor, and Norton replaced him with the Rhodesian racer Ray Amm. Duke's move spurred the British team to work harder, and throughout the season Amm did wonders riding the Norton single-cylinder. But the combination of Gilera and Duke won the championship.
For three consecutive seasons Gilera and Duke were an unbeatable combination. They won the world championship in 1953, 1954, and 1955, as well as a host of other races.

In 1956 the MV Agusta 500 four-cylinder, designed by Remor (who had also worked on the Gilera) and ridden by the new British star John Surtees, took the championship away from Gilera. The following year Duke was out of racing after the first races of the season because of an accident. But Libero Liberati and Bob Mcln-tyre, the Scot, won the title for Gilera. They also won the 350 class for championship brands with a 350 four-cylinder that was exactly like the 500. At the end of 1957 Gilera retired from racing.

Motorcycle: Gilera 500 Four-cylinder Manufacturer: Moto Gilera, Arcore Type: Racing Year: 1957
Engine: Gilera four-cylinder, four-stroke, with two-shaft overhead geared distribution. Displacement 499.4 cc. (52 mm. x 58.8 mm.)
Cooling: Air
Transmission: Five-speed block
Power: 70 h.p. at 10,500 r.p.m.
Maximum speed: Over 160 m.p.h. (with bell fairing)
Chassis: Double cradle, continuous, tubular. Front and rear, telescopic suspension
Brakes: Front and rear, central drum, double cam

Motorcycle: Gilera 500 Four-cylinder Manufacturer: Moto Gilera, Arcore Type: Racing Year: 1955
Engine: Gilera four-cylinder, four-stroke, with two-shaft overhead geared distribution. Displacement 492.7 cc. (52 mm. x 58 mm.)
Cooling: Air
Transmission: Five-speed block
Power: 65 h.p. at 10,000 r.p.m.
Maximum speed: Over 140 m.p.h.
Chassis: Double cradle, continuous, tubular. Front and rear, telescopic suspension
Brakes: Front and rear, central drum, double cam