23: Motor & Propeller

There’s a lot going on with motors and props. Thrust, torque, sound, strength, cage size, etc.

Misinformation on torque and other bits can be delivered with religious fervor. It’s still wrong. I’ve worked with other respected pilots and aerodynamic experts to get reliable info into the PPG Bible. Here are some highlights.

Here is a great video showing how a 2-stroke engine works and how a membrane carburetor works. It’s intent is to show servicing of Walbro carbs but it’s very informative.


All About Fuel

Extracting this much power from such tiny, lightweight motors, requires great care. The following will help you to make the most intelligent fuel choices for your favorite propulsion. Excerpted from Group K Technical Documents. See also Alcohol in Fuel,   Does AvGas...

Understanding Paramotor Torque & Twist

This is one of the most confusing aspects of understanding paramotor dynamics. The basics are like this (we’ll assume a belt-drive machine): The various torque effects conspire to twist your body left, the resulting redirected thrust now pushes your body left,...

Paramotor Overheating

Causes and cures of this motor killer Heat is a paramotor’s mortal enemy. Worst cases have the piston welding itself to the cylinder wall in the mother of all motor failures: a seizure. A close cousin is the piston burning a hole through it’s top. Molten...

Matching Propeller To PPG

Download the Prop Speed Spreadsheet to quicken your calculations. What’s the right prop for your paramotor? As you can imagine, it’s not a simple answer, but here are some criteria on which to choose. First some basics about props and engines to get you...