Steve201a

What is the difference between an electric "inrunner" and "outrunner motor and what type is generally used in a slow flier type aircraft?

Thanks!

Fliprob17

This is how I understand it, I try and only use outrunners, they just seem to be easier to deal with. The inrunners typical require a gearbox because they have a much higher rpm/kv rating. So you need the gearbox to slow them down, so you can throw a bigger prop on without *****g out the system. The outrunners typically run lower rpm/kv ratings, therefore no gearbox required. They both mount differently as well. The outrunner typically is a stick mount, while the inrunners sit in more of a carrier so to speak. I would recommend an outrunner.

jdetray

With an outrunner, the outer portion of the motor (the can) is the part that spins, while the inner part of the motor is fixed. With an inrunner, the inner portion of the motor spins, while the can is fixed.

Outrunners are generally best for spinning a large prop at relatively low RPM with relative high torque, which is what you need for either a slow flyer or a 3D type plane.

- Jeff