• Rare works machine
• Experimental four-valves-per-cylinder design
• Raced during the 1952 season only
• Offered for restoration

Italy's oldest surviving motorcycle manufacturer, Benelli was founded in Pesaro in 1911 by the six Benelli brothers, starting out as a general engineering firm repairing cars and motorcycles before turning to the manufacture of automotive and aircraft components in WWI. The firm diversified into the field of powered transport immediately after WWI, offering a two-stroke 'clip-on' power unit for attachment to a bicycle, and it was this 98cc engine, installed in a purpose-built set of cycle parts, that was used for the first proper Benelli motorcycle of 1921.

A couple of years later Benelli had a 125cc model in the range, and it was one of these, bored out to 147cc for the 175cc class, on which youngest brother Antonio ('Tonino') Benelli made his racing debut. By 1927 Tonino was racing a 172cc Benelli equipped with single-overhead-cam engine, winning almost as he pleased to take that year's Italian Championship. The SOHC 175 was superseded by a short-stroke twin-cam version from which was developed the first racing 250 of 1935. By this time Benellis were winning classic races outside their native Italy, but an accident to Tonino, which caused his retirement from racing, set back the factory's competition programme for the next couple of years.

Benelli was back in force for 1937 and the new 250 duly demonstrated its potential when Martelli won that year's Milan-Taranto long-distance classic. Two years later came the marque's most famous victory, when lone Benelli rider Ted Mellors won the 1939 Isle of Man Lightweight TT.

Its factory destroyed by the Allies and then looted by the Germans, Benelli took time to re-establish itself after the war. Fortunately, the racing machines had been hidden away and survived intact, providing the Italian concern with a valuable springboard from which to renew its Grand Prix campaign. Rivals Moto Guzzi secured the first post-war 250cc World Championship in 1949, but Benelli struck back the following year when works rider Dario Ambrosini became champion at the end of a season that included wins in three of the four 250 rounds: Switzerland, Italy, and the Isle of Man TT. He finished 2nd in the other round (the Ulster GP) to crown a season of masterly dominance. Sadly, Ambrosini's death at the French Grand Prix in 1951 effectively put an end to Benelli's international efforts.

Nevertheless, in the immediate aftermath of Amrosini's death Benelli continued to develop and race the 250. At the beginning of 1952 the machine appeared with 19" wheels, a five-speed gearbox, larger fuel tank and a small fork-top fairing. An engine equipped with a four-valve cylinder head was tested also. Riders Luigi Ciai, Alano Montanari and Leslie Graham took part in a few races, the best result being Graham's 3rd place at the Swiss Grand Prix, a significant achievement considering that on the tricky Bremgarten circuit he was unable to select 5th gear.

Unable to find a permanent replacement for the great Ambrosini, Benelli quit the Grand Prix scene in 1953 and it would be 1959 before they attempted another serious World Championship campaign. When they did, it was with a new, short-stroke (70x64.8mm) two-valve engine.

Offered for restoration and sold strictly as viewed, this ultra-rare and incomplete Benelli works racer comes with a selection of original photographs taken during the 1952 season.