Honda Releases the GX25-the World's Lightest 4-Stroke Engine
April 22, 2002, Japan
April 22, 2002-Today, Honda Motor Co., Ltd. announced the release of the new GX25 25cc displacement, 360°-inclinable 4-stroke engine. At 2.78kg, this engine is the lightest of its kind in the world*1, making it the ideal power source for a variety of hand-held power equipment. The GX25 will be available at Honda power equipment dealers throughout Japan from June 27. Honda will also be supplying the engine to other power equipment manufacturer's on an OEM basis.
The GX25 was developed to meet three design objectives: to be the lightest in the world; to be 360°-inclinable; and to provide outstanding environmental performance.
The engine employs the world's most compact*2 oil-immersed timing belt OHC configuration, making it possible to incorporate the valve train into the oil reservoir for substantial weight and volume savings. Honda's original rotary slinger pumping lubrication system ensures full oil lubrication no matter what the engine angle, allowing it to be continuously operated or stored in any position.
The GX25 offers superb environmental performance, achieving a top-class*3 ranking under American EPA (Environmental Protection Agency) Phase 2 regulations-the most stringent in the world. It also delivers an outstanding balance of all-round performance, with a power-to-weight ratio of 0.29kW/kg (among the highest in the hand-held, 4-stroke engine category), combined with low noise and low vibration, for efficient, carefree operation.
*1,2 As of April 2002
*3 EPA: Class I-A (under 65cc displacement) and Class IV (20cc~50cc displacement)
GX25 360°-inclinable 4-stroke engine
| ●Annual projected sales nationwide: | 155,000 units |
| ●Manufacturer's suggested retail price (consumption tax not included): | ¥30,000 |
Other Features of the GX25
Smooth starting and superb acceleration
- Mechanical decompression results in a class-beating starter rope pull weight of just about 7 kgf-so light that anyone can start it with ease. A newly developed accelerator pump-equipped carburetor result in excellent acceleration immediately after startup on par with that of a 2-stroke.
High environmental performance
- A Honda e-SPEC engine that achieves top-class*4 ranking in American EPA (Environmental Protection Agency) Phase 2 regulations-the most stringent in the world.
- Achieves top-of-class fuel economy and oil consumption.
- Oil-immersed timing belt reduces mechanical noise.
- Lighter pistons and other parts create less vibration, resulting in less fatigue during hand-held operation.
- *4EPA: Class I-A (under 65cc displacement)
Maintenance
- The engine is designed to allow the cover to be removed by loosening a single bolt. The air cleaner cover can be removed and replaced with just one hand.
Design
- Full-cover construction reduces snagging on branches or other objects during operation. Designed with a low center of gravity and a shape that doesn't catch on the operator's elbow, for greater operability and maneuverability.
New Power Red coloring heightns brand identity for Honda power products. The new color will be gradually introduced to all power product engines, starting with the release of products featuring the GX25.
●Specifications
| Model Name | GX25 |
| Type | e-SPEC air-cooled 4-stroke single-cylinder OHC |
| Displacement(cm3) | 25 |
| L x W x H (mm) | 192×221×230 |
| Outfitted Weight (kg) | 3.25 |
| Dry Weight (kg) | 2.78 |
| No. of Cylinders / Bore x Stroke (mm) | 1/35×26 |
| Max. Power [kW (PS)/rpm] | 0.81(1.1)/7,000 |
| Max. Torque [N•m (kg•m)] | 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) | 0.55 |
| Fuel Consumption (g/kW-h [g/PS-h]) | 340(250) |
| Oil Reservoir Capacity (L) | 0.08 |
| Carburetor | Diaphragm type (overflow return) |
| Ignition | Transistorized magneto |
| Spark Plug | NGK CM5H/CMR5H |
| Starter | Recoil type |