FXS 1340 Low Rider

1981 Harley-Davidson FXS 1340 Low Rider Technical Analysis & Specification Breakdown

At the heart of the 1981 Harley-Davidson FXS 1340 Low Rider sport touring motorcycle, Harley-Davidson features a 1337 cc (81.6 cu in) air-cooled v2, four-stroke configuration. In factory specification, peak output is rated at 67 HP (48.9 kW) at 5,800 rpm while maximum torque reaches 90.8 Nm (67 lb-ft) at 3,600 rpm, transferring power to the rear wheel through a 4-speed gearbox and chain final drive. With a specific output of 50.1 HP per liter and a 2,200 rpm working window between peak torque (3,600 rpm) and peak power (5,800 rpm), the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.

On the scales, the FXS 1340 Low Rider measures 289 kg (637 lbs) wet (curb), translating to a power-to-weight ratio of 0.23 HP/kg (4.31 kg per horsepower). Rider ergonomics and chassis geometry center around a 685 mm (27 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops. The 15.5-liter (4.1 US gal) fuel tank supports practical everyday commuting and weekend road stints, while factory top speed is listed at 165 km/h (103 mph).

Within MotoLibrary's Harley-Davidson archive, this model family spans 2 indexed model years from 1980 to 1981, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.