Model J

1918 Harley-Davidson Model J Technical Analysis & Specification Breakdown

Positioned in Harley-Davidson's allround motorcycle lineup, the 1918 Harley-Davidson Model J features a 989 cc (60.4 cu in) v2, four-stroke configuration. In factory specification, peak output is rated at 17 HP (12.4 kW) at 3,200 rpm, transferring power to the rear wheel through chain final drive. With a specific output of 17.2 HP per liter, the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.

On the scales, the Model J measures 145 kg (320 lbs) dry, translating to a power-to-weight ratio of 0.12 HP/kg (8.53 kg per horsepower).

Within MotoLibrary's Harley-Davidson archive, this model family spans 15 indexed model years from 1915 to 1929, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.