Introducing the SP-28 CR: A Reliable 2-Stroke Engine
The SP-28 CR, a 2-stroke single-cylinder engine with a displacement of 28 ccm, has established itself as a cornerstone in our product range. renowned among industry experts for its durability and reliability, this engine has been a trusted choice for many years.The Sky Power SP-28 CR remains our most sought-after model, particularly ideal for fixed-wing aircraft within the “under 55 lb” or “up to 25 kg” category of Unmanned Aerial Systems (UAS).
Engine Specifications and Features
the 3W-International SP-28 CR engine comes standard with a single spark plug and ignition unit, featuring a rear-mounted carburetor (CR). Both the cylinder and crankcase are crafted from aluminum, a design that has been in production for over a decade.
- Lightweight and robust, the carbureted version stands out in its class.
- the carburetor automatically adapts to both engine performance and environmental conditions.
- users report flight durations of up to 24-28 hours with this setup.
Technical Specifications
| Engine Type | Single-Cylinder Gas Engine |
| Displacement | 28 ccm / 1.71 cu in |
| Output Power | 2.2 HP / 1.6 KW |
| RPM Range | 2500 – 10000 RPM |
| Weight | 2.95 lbs (1.34 kg) including ignition system |
| Crankshaft Design | 3 ball bearings |
| Oil to Gasoline Ratio | 1:50 / 2% mixture |
| Operating Voltage | 6 – 8.4 V DC |
| Bore Size | 1.42 inches (36.00 mm) |
| stroke Length | 1.10 inches (28.00 mm) |
| Torque Output | 2.3 Nm @ 6600 RPM |
