Understanding RC Electric Motors And How To Find The Right One

29 May 2019
Larry Ficks

The world of remote controlled vehicles can be the source of endless entertainment, and the more you get into it the more interesting it becomes. With so many different types of RC vehicles and all the different types of parts that come with them, the RC world is huge and leaves a lot of space for customization. You can get a basic model and an RC electronics kit to make it as powerful as you want. For example, you can replace a brushed motor with a brushless one to make your RC vehicle more powerful. Or, you can replace your battery with a more powerful one to allow you to drive your RC vehicle for longer. You can install new lighting, cameras, radio gear, ESC, etc. to make your vehicle stand out, or even build one.

When it comes to buying an RC electronics kit, the most sought-after upgrades are motors. RC electric motors are available in two variants – brushless motors which require an external controller to switch the power through the coils, and brushed motors which feature small brushes that switch the power through the coils.

Brushless motors are more powerful and more efficient, and they can handle higher torques and speed. Furthermore, they last longer as they don’t have brushes which wear out. They’re typically available in in-runner and out-runner styles. In-runner brushless motors feature permanent magnets and have a non-rotating housing. Out-runner brushless motors, on the other hand, feature permanent magnets on the outside and the entire housing spins with the help of an axle. Out-runner motors offer more torque but less speed, and they’re generally used with larger propellers. In-runner motors offer less torque but can reach very high speeds, making them more suitable in geared applications like RC cars, and with small propellers.

The power of motors in the RC world is measured using Kv. Most people think that Kv stands for kilovolts, but it actually represents rotations per minute per volt. So, for instance, if you have a 200Kv motor, it will rotate at 600rpm at 3V. The lower the Kv rating of the motor, the more torque it will have but less speed, and the higher the rating, the more speed but less torque it will have. You can find a large selection of RC electric motors online, all of which vary in power, efficiency, and, of course, cost. Brushed motors are more affordable than brushless, but if you’re looking to upgrade, then you’re probably best off with a brushless model.