Zenoah G-25


The Zenoah G-25 is a single cylinder, two stroke, carburetted aircraft engine, with optional fuel injection, designed for use on ultralight aircraft[1][2]

Zenoah G-25
Type Single cylinder two-stroke aircraft engine
National origin Japan
Manufacturer Zenoah


The Zenoah G-25 is equipped with single capacitor discharge ignition and a single Mikuni slide-type carburetor. It is equipped with a recoil starter system or optionally electric start and a 2.5 or 2.8:1 belt reduction drive.[1][2][3]

The engine runs on a mixture of unleaded auto fuel and oil.[1][2]

Producing 22 hp (16 kW) at 6600 rpm, the G-25 competed in the early 1980s ultralight powerplant market against the similar Rotax 277. Production of the engine was completed in the late 1980s and today only used engines and parts are available.[1][2]


Specifications (G-25B-1)Edit

Data from Cliche & Tennessee Propellers[1][2]

General characteristics

  • Type: Single cylinder, two-stroke aircraft engine
  • Bore: 72 mm (2.8 in)
  • Stroke: 59.5 mm (2.3 in)
  • Displacement: 242 cc (14.78 cu in)
  • Length: 11.81 in (300.0 mm)
  • Width: 11.57 in (293.9 mm)
  • Height: 14.84 in (376.9 mm)
  • Dry weight: 51 lb (23.1 kg)




  1. ^ a b c d e Cliche, Andre: Ultralight Aircraft Shopper's Guide 8th Edition, page G-8 Cybair Limited Publishing, 2001. ISBN 0-9680628-1-4
  2. ^ a b c d e Tennessee Propellers (n.d.). "Zenoah Engines". Retrieved 2009-12-24.
  3. ^ Tennessee Propellers (2000). "Zenoah Engine Retail Pricing". Retrieved 2009-12-24.