After the Second World War Benelli only built motorcycles up to 250 cc. To conquer the big American market, where British twins ruled, the make decided to build a big twin. A 350 was planned at first, but it became a 650.

The engine was designed by Piero Prampolini, who had also drawn Benelli’s four-cylinder racers. Luigi Benelli drew the double cradle frame, and racer Renzo Pasolini helped with development. Actor Steve McQueen, Benelli’s ambassador in America, suggested a Métisse-style frame to improve the handling.

The first prototype stood at the 1967 Milan motorcycle show. Because of a lack of money and disagreement between the Benelli brothers, production did not start until 1970. The first bikes went to the USA in 1970, Europe followed in 1971 and Germany in 1972. By then the Honda CB750 and Kawasaki H1 were already there, and the Tornado had a hard time. It was also sold as a Motobi, Benelli’s sister make.

In 1972 Alejandro de Tomaso bought the company. That same year the much improved 650 S came, and in 1973 the last version, the S2. In Germany the Tornado was offered until 1976. About 3,000 were built in total, about half of them sold in Italy. To prove its reliability an S2 rode non-stop through Italy for 25 hours, with 18 well-known riders including Tarquinio Provini and Walter Villa: 2,612 km.

Tornado (1970–1971): no starter motor, with a belt-driven dynamo. The very first bikes had a single 30 mm carburettor, after that two of 29 mm.

650 S (1972): electric starter, better balanced crankshaft, higher compression, different gear ratios, Veglia instruments, rubber mounting and bar-end weights against vibration. The dynamo moved to the end of the crankshaft.

650 S2 (1973): even higher compression for more low-down pulling power, more rubber mounting, a humped dual seat and a clear handlebar fairing.

American and European versions differed in details such as handlebars and dual seat.

The engine itself is known as robust and oil-tight if well maintained. Unusual: the crankshaft turns ‘backwards’, so the hot side of the cylinder faces forward into the cooling air. The Tornado does have a few known weak points.

Vibration. Above about 4000 rpm the engine vibrates a lot. Despite rubber mounting, bolts, nuts and bulbs shake loose.

Ignition. The ignition sits under the dynamo. Adjusting it is ‘real work’; Motorrad recommends a modern electronic ignition.

Handling. The low-speed behaviour was criticised, because the engine sits high in the frame. The suspension is firm.

Front brake. The first bikes had a double twin-leading-shoe brake. American buyers found it too fierce, so a double single-leading-shoe brake was fitted.

In 2014 Motorrad called the parts situation ‘comparatively good’, with specialist Benelli-Bauer in Germany and the German Benelli-IG as a club. Body and sheet-metal parts are scarce, though.

Price indication. We found no recent, reliable price source. Motorrad wrote in 2014 that good originals and well-made conversions often fetched more than € 4,000. On the classic site Classic Trader there was no Tornado for sale in November 2026, so supply is small. Assume prices may have risen since 2014 and compare current adverts yourself.