Honda Releases The All New GX25 4-Stroke Handheld Engine

7/19/2002 7:18:54 PM

American Honda Motor Co., Inc. recently launched the all-new GX25 mini four-stroke engine. With a displacement of 25 cubic centimeters and weighing only 2.78kg (6.1 pounds), the 360o inclinable GX25 is the lightest and most compact engine of its kind in the world, making it the ideal power source for a variety of handheld power equipment applications.

The GX25 was introduced nationally by Honda Engine dealers in the summer of 2002, and also is supplied to other power equipment manufacturers on an OEM basis - at a price consistent with that of the GX22 it replaces.

"This is a very important engine for us and is an example of our confidence in four-stroke technology for handheld applications," said Scott Conner, Honda Engines senior manager. "It addresses the weight issue that is so important to users of handheld equipment."

The size and weight of the GX25 were reduced through the use of an oil-immersed timing belt overhead-cam configuration that makes it possible to incorporate the valve train into the oil reservoir. This results in an overall weight comparable to that of a two-stroke engine and an unparalleled power-to-weight ratio of 0.29kW/kg.

Ease of start-up and rapid acceleration are achieved using mechanical decompression that results in a class-leading starter rope pull weight of 7.2kgf, and a new accelerator pump-equipped carburetor. This, in conjunction with a super-lightweight flywheel, results in performance on par with that of a two-stroke engine.

GX25's four-stroke technology uses a unique rotary slinger pumping lubrication system, allowing it to be operated or stored in any position, and providing for low noise and vibration to minimize operator fatigue. In keeping with Honda's commitment to environmental leadership, GX25 also has achieved a top-class rating under the EPA's stringent Phase 2 emissions regulations, while delivering unsurpassed fuel economy and oil consumption.

GX25's full-cover design reduces snagging on branches or other objects during operation, but can be removed by loosening a single bolt for ease of maintenance. Additional measures were taken to ensure a low center of gravity for enhanced maneuverability.

American Honda Motor Co., Inc. is the world's largest producer of engines. A world-class reputation for durability, quality, reliability, and ease of operation under the most extreme conditions makes Honda Engines the recognized choice for the construction and rental industries.

GX25 four-stroke engine specifications

Model Name



e-SPEC air-cooled 4-stroke single-cylinder OHC

Displacement (cm3)


L x W x H (mm)

192 x 221 x 230

Outfitted Weight (kg)


Dry Weight (kg)


No. of Cylinders / Bore x Stroke (mm)

1 / 35 x 26

Maximum Output / Engine Speed (kW [PS] / rpm)

.081 [1.1] / 7,000

Maximum Torque (N-m[kg-m] / rpm)

1.25 [0.13] / 5,000

Direction of Rotation

Counterclockwise (viewed from output shaft side)

Fuel Type

Automotive-grade unleaded gasoline

Fuel Tank Capacity (l)


Fuel Consumption (g/kW-h [g/PS-h])

340 [250]

Oil Reservoir Capacity (l)



Diaphram type (overflow return)


Transistorized magneto




Recoil type

Editor's Note:

Honda Power Equipment, a division of American Honda Motor Co., Inc., manufactures and markets a complete range of outdoor power equipment, including outboard marine engines, general purpose engines, generators, lawnmowers, pumps, snowblowers, tillers and trimmers for commercial, rental and residential applications. Its comprehensive product line is powered exclusively by environmentally advanced 4-stroke engines.

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