Benelli four-cylinder

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The Benelli four-cylinder was a racing motorcycle from the Italian motorcycle manufacturer Benelli , which was used in the motorcycle world championship from 1962 to 1969. 1969 won Kel Carruthers the title in the class up to 250 cc.

History and technology

As early as 1939, Benelli developed a prototype of a four-cylinder, four- stroke engine with a displacement of 250 cm³, which was designed in a highly modern manner with two overhead camshafts and spur gear drive. In 1960 the idea of ​​the prototype was taken up again and a newly designed four-cylinder with magneto ignition was presented, which, however, was not used in racing until 1962. With a bore of 44 mm and a stroke of 40.5 mm, the engine developed around 29 kW (40 hp) at 13,000 rpm. Not very successful internationally, however, the driver Tarquinio Provini won the Italian national championship on the Benelli in 1965. In March 1965, the four-cylinder engine received a double hydraulically operated disc brake on the front wheel for test drives .

In 1966 a 350 cc version of the four-cylinder engine with 44 kW (60 hp) at 14,000 rpm was developed, which was first used in September 1967. Silvio Grassetti thus achieved second place in his class at the Grand Prix of Nations in Monza . A 500 cc version under Renzo Pasolini surprisingly beat Giacomo Agostini in the spring race in Modena in 1967 . With the 350 Benelli, Pasolini came second in the 1968 motorcycle world championship .

In 1969, Kel Carruthers won the second world championship title for Benelli in the class up to 250 cc on the further developed four-cylinder engine with eight-speed transmission. When a change in the regulations in 1970 limited the class up to 250 cm³ to two cylinders and six gears, the end came for the four-cylinder with 250 cm³. Until the introduction of Moto2 (2010), this would also be the last title on a four-stroke engine.

After the takeover of Benelli by Alejandro de Tomaso , all motorsport activities were stopped in 1972. In the class up to 350 cm³, Walter Villa drove the four-cylinder Benelli until the beginning of 1973. On May 20, 1973, Walter Villa is said to have caused the tragedy of Monza , with the death of Jarno Saarinen and Renzo Pasolini , by leaking oil on the 350 cm³ Benelli .

Web links

literature

  • Mick Walker: Italian motorcycle classics. Volume 2 racing machines . Schrader Motor Album. 1991., ISBN 3-922617-85-9 .

Individual evidence

  1. ↑ Mick Walker: Volume 2 racing machines., P. 30.
  2. ↑ Mick Walker: Volume 2 racing machines., P. 34.
  3. ↑ Mick Walker: Volume 2 racing machines., P. 34.
  4. ↑ Mick Walker: Volume 2 racing machines., P. 36.