1955 Simplex
Country: United States
Engine: Air-cooled, single cylinder, 2-stroke
Ignition: Flywheel magneto, twin spark plugs
Bore x stroke: 2in x 2.534in
Displacement: 129cc
Valves: Rotary inlet valve in crankshaft
Fuel system: Tillotson carburetor
Transmission: Variable speed, with centrifugal-operated vee pulleys
Suspension: Front leading link fork, rigid rear
Brakes: Rear drum
Weight: 135lb
Top speed: 45mph
The Simplex was a very basic lightweight motorcycle with many features dating back to the early machines of the 1910s and 1920s, such as the belt drive. This bike would be a logical upgrade from a Whizzer-powered bicycle — economical, easy to operate and relatively inexpensive. The Salisbury-type clutch gave infinitely variable automatic gear ratios that greatly improved the performance.