Most paramotors fly on small two-stroke engines because they are light, simple and powerful for their size. Four-stroke engines are heavier but quieter and more fuel-efficient, and electric motors are quiet and clean but limited in flight time. The right choice depends mainly on your weight, your wing, how far you want to fly, and how much maintenance and noise you are willing to live with. Thrust at the propeller, not horsepower on a spec sheet, is the figure that decides if a launch will be comfortable.
What is in a paramotor power unit
- Engine. A small single-cylinder or twin, air-cooled in most designs, though some use water cooling.
- Reduction drive. A belt or gear set that slows the propeller to a more efficient speed than the engine itself turns.
- Propeller and cage. A large, slow-turning prop in a protective cage, usually made of wood or composite. Prop diameter and pitch are matched to the engine and wing.
- Centrifugal clutch. Many engines include one so the propeller does not turn at idle.
- Carburetor or fuel injection, exhaust, ignition, starter (pull or electric), throttle and a kill switch.
- Fuel tank, which must be consistent with Part 103's limit of 5 U.S. gallons if the machine is to be flown as an ultralight.
Most paramotor engines come from a small number of specialist makers, many of them in Europe. Models and published figures change from year to year, so compare current manuals and specification sheets rather than old reviews or forum posts.
Two-stroke, four-stroke and electric compared
| Type | Strengths | Trade-offs |
|---|---|---|
| Two-stroke | Light weight, strong power for the size, simple construction, widely available and often easy to service. | Needs oil mixed with the fuel, louder, thirstier, and produces more exhaust smoke. |
| Four-stroke | Quieter, better fuel economy, no premix, smoother running. | Heavier and more complex, usually more costly, and fewer models are made for ultralight use. |
| Electric | Very quiet, no fuel or exhaust, minimal vibration, simple starting. | Shorter flight time than gasoline, battery weight, charging logistics and careful battery handling. |
A pilot who wants long cross-country flights will weigh fuel economy and endurance. A pilot who flies near homes may weigh noise. A heavier pilot needs more thrust. The practical advice is to fly different setups through a school or experienced friends before committing.
Thrust, power and pilot weight
Static thrust is the force the propeller pulls with while you stand still. You need enough to accelerate with the wing overhead and climb away safely, with some margin for hot days and for the extra weight of fuel. Lighter pilots can use compact engines and smaller props. Heavier pilots generally need more thrust, which means a larger engine, a larger prop, or both, and the additional weight and fuel consumption that come with them. Manufacturers publish thrust figures, but compare them at similar conditions. The choice also connects to your wing, because a wing flown near the heavy end of its range needs more power to get going. The guide to choosing a wing explains the weight range.
Fuel and what to put in the tank
Each engine's manual states the fuel grade, the oil type and, for two-strokes, the mixing ratio. Follow it exactly. Fuel quality matters. Pump gasoline in much of the country contains up to 10 percent ethanol, which absorbs moisture and can degrade rubber parts and some fuel system components. Some engine makers advise against it or limit it, and others allow it. Storage matters just as much: fuel left in the tank for weeks deteriorates, and hot weather speeds it up. Use approved containers, mix fresh, and do not store the aircraft with a full tank of old mix. In Florida's heat, vapor can form in fuel lines, so read what your manual says about hot-weather operation.
Heat, temperature and gauges
Air-cooled engines depend on airflow, and a paramotor on the ground, or flying slowly under power in heat and humidity, can run warm. Many pilots install cylinder head temperature or exhaust gas temperature gauges to see trouble developing. Hot, humid air is also less dense, which costs power and climb, so the same setup feels weaker on a hot afternoon than on a cool morning. This is another reason that dawn flights are attractive in warm months, as described in the weather guide.
Maintenance in practice
- Spark plugs, filters and fuel lines are consumables and are inspected at regular intervals.
- Carburetors need clean fuel and occasional cleaning. Stale fuel is a frequent cause of rough running.
- Bolts, mounts and the reduction drive need regular attention, because vibration loosens things.
- Exhaust parts, springs and bearings wear and need replacing at intervals the manufacturer states.
- Propellers are inspected before every flight. Even a minor strike can crack a blade.
The pre-flight checklist shows where engine checks fit into each flight, and the care guide covers corrosion in coastal conditions.
Noise and neighbors
A paramotor is loud. Early-morning flights are popular for good reason, but they are also when neighbors sleep. Local nuisance and noise rules can apply, and a landowner who is annoyed by noise is a landowner who will not let you fly again. Choosing a quieter setup, climbing away from homes, and picking fields with some distance all help.
Frequently Asked Questions
Are two-stroke or four-stroke paramotor engines better?
Neither is better in every case. Two-strokes are lighter and more powerful for their size. Four-strokes are quieter and more economical but heavier. The choice should match your weight, wing and priorities.
How much fuel can a paramotor carry?
Under Part 103, a powered ultralight may have a fuel capacity of no more than 5 U.S. gallons. Most paramotors carry less than that.
Can I use regular pump gasoline?
It depends on the engine. The manual states the required fuel and oil. Many manuals address ethanol, so check what yours says before filling up.
Is an electric paramotor practical?
For short flights, yes, and the quiet is a real benefit. Flight time is limited by battery capacity, so it suits some pilots and not others.
How often does a paramotor engine need service?
Follow the manufacturer's schedule. Routine items like plugs and filters are checked often, while major components are serviced by hours or condition.