Built around Simplex's allround motorcycle platform, the 1942 Simplex Automatic relies on a 130 cc (7.9 cu in) single cylinder, two-stroke powerplant. In factory specification, peak output is rated at 4 HP (2.9 kW) at 4,000 rpm, transferring power to the rear wheel through belt final drive. With a specific output of 30.8 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 Automatic measures 61.2 kg (135 lbs) dry. Rider ergonomics and chassis geometry center around a 1,194 mm (47 in) wheelbase engineered for quick, flickable steering geometry. The 9.46-liter (2.5 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Within MotoLibrary's Simplex archive, this model family spans 18 indexed model years from 1942 to 1960, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
30.8 HP/L
Engine
Displacement130.0 ccm (7.93 cubic inches)
Engine TypeSingle cylinder, two-stroke
Engine DetailsSingle cylinder, two-stroke
Power4.0 HP (2.9 kW)) @ 4000 RPM
Compression6.5:1
Bore x Stroke50.8 x 64.3 mm (2.0 x 2.5 inches)
Fuel SystemCarburettor. Tillottson
Fuel ControlOverhead Valves (OHV)
IgnitionMagneto and dual spark plugs
Transmission
Final DriveBelt (final drive)
Chassis
Frame TypeDuplex loop
Front SuspensionShort rocker arms and two coil springs
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
