900 Sei

1981 Benelli 900 Sei Technical Analysis & Specification Breakdown

Engineered by Benelli for the classic motorcycle segment, the 1981 Benelli 900 Sei relies on a 905 cc (55.2 cu in) air-cooled in-line six, four-stroke powerplant. In factory specification, peak output is rated at 80 HP (58.4 kW) at 8,300 rpm, transferring power to the rear wheel through a 5-speed gearbox and chain final drive. With a specific output of 88.4 HP per liter, the engine character is indicating a tractable, stress-free state of tune focused on everyday usability and broad torque delivery.

On the scales, the 900 Sei measures 249 kg (549 lbs) wet (curb), translating to a power-to-weight ratio of 0.32 HP/kg (3.11 kg per horsepower). The 17-liter (4.5 US gal) fuel tank supports practical everyday commuting and weekend road stints, while factory top speed is listed at 193 km/h (120 mph).

Within MotoLibrary's Benelli archive, this model family spans 13 indexed model years from 1978 to 1990, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.