SX 250

1977 Harley-Davidson SX 250 Technical Analysis & Specification Breakdown

Positioned in Harley-Davidson's cross - motocross motorcycle lineup, the 1977 Harley-Davidson SX 250 utilizes a 243 cc (14.8 cu in) air-cooled single cylinder, two-stroke layout. In factory specification, peak output is rated at 20 HP (14.6 kW) at 7,000 rpm, transferring power to the rear wheel through a 5-speed gearbox and chain final drive. With a specific output of 82.3 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 SX 250 measures 125 kg (276 lbs) wet (curb), translating to a power-to-weight ratio of 0.16 HP/kg (6.25 kg per horsepower). The 10.5-liter (2.8 US gal) fuel tank supports practical everyday commuting and weekend road stints, while factory top speed is listed at 115 km/h (71 mph).

Within MotoLibrary's Harley-Davidson archive, this model family spans 2 indexed model years from 1976 to 1977, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.