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This 1977 Benelli Sei is an Italian motorcycle featuring its original 6-cylinder 747cc engine that was purchased from its long-term owner who had the bike since 1979. The 750 Sei is notable as the first six-cylinder engine to be offered in a production motorcycle. This bike was ridden regularly until 1995, at which time it received a mechanical and cosmetic restoration. The engine was rebuilt with all new components, and the chassis and ancillaries were fully refurbished. The odometer was zeroed and the bike has done 16k miles in the last 20 years.
The 750 Sei was envisioned by Alejandro de Tomaso and was produced from 1973 to 1989. De Tomaso wanted it to become Italy’s go-to sporting motorcycle with styling by Ghia. The Sei was heavily marketed when launched, and although it was well liked by riders, it could never manage to outsell its Japanese competitors.
Red paint is in good condition and the chrome trim, fenders, and engine components all look nice. Badging is accounted for and in good shape. The bikini front fairing is a period item that can easily be removed for a more sporty look.
The bike is largely stock, with the exception of an aftermarket exhaust setup, seat cover, and turn indicators. Veglia gauges are said to work properly, though the tachometer face is cracked.
The aftermarket seat is in good condition with no tears or stitching issues. A new seat cover is also included.
Up front, handling is achieved with black and chrome 38mm Marzocchi telescopic forks and twin disc-brakes, while the rear wheel utilizes twin shock suspension and features drum brakes. the bikini front fairing is a period item that can easily be removed for a more sporty look.
The 747cc air-cooled inline six-cylinder engine was overhauled by the previous owner in 1995. The engine was modeled on the four-cylinder Honda CB500, with two extra added cylinders. The engine produced a healthy 76hp at 9000 rpm when new, and could propel riders up to 127mph.
The 750 Sei is famous for the sound from its six mufflers. Although this example currently wears an aftermarket unit, a complete new 6 into 6 exhaust system is included. The system can be seen above with period seat cover and new set of stock turn indicators, also included in the sale.
Even with 6-cylinders, the width of the bike was kept at bay by positioning the alternator behind the cylinders. Cooling was increased with air passages between the cylinders, and three Dell’Orto VHB 24 mm carburetors blend air and fuel efficiently. The Benelli 750 Six remained the only six-cylinder motorcycle in production until the Honda CBX was introduced in 1978. Service records from the ’95 resto are included, and the bike carries a clean Florida title.