1955 aermacchi hd 150 zeffiro Technical Analysis & Specification Breakdown
Positioned in aermacchi's scooter motorcycle lineup, the 1955 aermacchi hd 150 zeffiro pairs a 148 cc (9 cu in) air-cooled single cylinder, two-stroke architecture with road-focused gearing. In factory specification, peak output is rated at 6 HP (4.4 kW) at 4,500 rpm, transferring power to the rear wheel through a 3-speed gearbox and chain final drive. With a specific output of 40.5 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 hd 150 zeffiro measures 92 kg (203 lbs) dry, translating to a power-to-weight ratio of 0.07 HP/kg (15.33 kg per horsepower).
Within MotoLibrary's aermacchi archive, this model family spans 6 indexed model years from 1955 to 1960, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
40.5 HP/L
Power-to-Weight
0.07 HP/kg (15.33 kg/HP)
Engine
Displacement148.0 ccm (9.03 cubic inches)
Engine TypeSingle cylinder, two-stroke
Engine DetailsSingle cylinder, two-stroke
Power6.0 HP (4.4 kW)) @ 4500 RPM
Compression6.5:1
Bore x Stroke57.0 x 58.0 mm (2.2 x 2.3 inches)
Fuel SystemCarburettor. DellÓrto
CoolingAir
Transmission
Gearbox3-speed
Final DriveChain (final drive)
ClutchWet multiplate
Performance
Top Speed90.0 km/h (55.9 mph)
Fuel Consumption2.80 litres/100 km (35.7 km/l or 84.01 mpg)
Greenhouse Gases65.0 CO2 g/km. (CO2 - Carbon dioxide emission)
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.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
