RC Motor Sizes 

The Ultimate Guide on Picking the Right RC Motor Sizes 

Having a drone for hobby or passion, whatever the reason, you must understand your drone and its components. 

It becomes a must when you have checked the motor size of your drone.

How to figure out RC motor sizes then?

RC motor size consists of many things, motor length, shaft diameter, and many more. You can find out different parameters of a motor just by figuring out the size. There are many conventions for motor sizes. They depend on the type of motor you are using.

If you really want to figure out the perfect motor for your drone, you must know every single thing about the motor sizes.

Don’t be restless!  I offer you such an article that has the necessary things you can learn.

Grab your boots and buckle up. It’s time to find some motor!

RC Motor Sizes Considering Different Components

The first thing that you would check about any RC motor is its size. Yes, size is an important factor when it comes to rc wheel nuts too. 

Source: importitall.co.za

Generally, when you say RC motor size, it includes the following things:

  • The diameter of the motor
  • The length of the motor
  • The diameter of the shaft
  • Length of the motor
  • Stator height
  • Stator width

The diameter and the length of the motor are the prime parameters that define the RC motor size.

Understanding The Convention

Now RC motors can be of different types. Some are brushless, some are brushed

However, different motors have different convention systems. You have to know the perfect convention to find the best motor. Otherwise, you might get confused just like the blinking light of the battery.

When It’s Brushless Motor

RC Brushless motors have a standard custom for displaying their parameters. 

There’s a number written on the body of the motor. This works as an RC brushless motor guide for sizing. The first two digits of the number are defining the diameter of the motor. 

Source: nidec.com

The next two digits will give you the length of the machine. 

In this way, you can easily figure out the primary information on RC brushless motor sizes.

A point to remember, the information you got on the length and diameter of the machine, are all given in millimeters. 

Let us have a glimpse of some well-known brushless motors:

If It’s Brushed

Since the brushless motor size is explained, what about the brushed motor?

Technically, there is no specific convention for a brushed RC motor, when it comes to size.

Every RC brushed RC motor has a number in its name. Well, that number is none other than the length of the RC brushed motor. 

Source: cs.uaf.edu

Besides, you can check on the RC motor sizes chart. You can easily find the prop size, motor diameter, motor length, and other required parameters.

Speaking of motors but seeing no motors? This is not gonna happen. Here are a few brushed motors:

What are we waiting for then? Let’s have the best motor to make your RC car run in the cold!

People seem to love the brushless motors for running their RCs.

Perks of RC Motor Sizes

Just like knowing your RC motor’s turning rate knowing the RC motor sixes can be beneficial. How you may ask? 

Clarification of the RC motor sizes can give you below discussed benefits:


The RPM of an Rc motor can be easily influenced by the stator size. 

If the height of the stator is increased, you will gain more energy at a higher value of RPM. 

On the other hand, if you increase the stator width, you will get a bigger value of torque even at the lowest possible value of RPM.

It’s because the size of the magnet inside the motor varies. 

When the stator height is bigger, this means the size of the magnet is comparatively more than the coil. 

As a result, the power of the motor increases and so does the RPM.

Similarly, increased stator width means an increased area for the inner magnet of the motor. This ultimately increases the torque. 

So, you can get more torques.


The size of the RC motor also manipulates the torque of the motor.

If the length of the motor is big, the value of the torque increases. As the length of the motor increases, the overall volume or size of the motor increases. 

As a result, the torque increases.

If you have two motors of the same radius but different, then which one will produce more torque? Obviously, the one with a bigger length!

The Size of The Drone

Believe it or not, ultimately the size of the RC drone can decide the fate of the drone itself!

When the volume of the Rc motor gets boosted, it also boosts up the value of the RPM. 

This more RPM does not only conserve your energy usage or increase efficiency but also allows you to go for more heavy-duty. 

In other words, higher torque motors can make heavier drones fly. 

So, if you like bigger drones over smaller ones, grab the RC motor with a higher volume.

A Gentle Reminder

Whoa, RC expert! We’ve learned a lot about RC motor sizes. However, there’s a tiny little piece of this “RC motor’ cake still left. 

Here are some golden rules to keep in mind, especially when it’s the size of the RC motor.

Frame Figuring

Check the size of the drone. There are many types of RC drones out there. 

You have to check the frame size of the drone.

Different props need different RPM values to produce an efficient thrust. 

Propeller Size

The spinning of a propeller can vary. So before choosing a motor size, select your propeller. 

Then go for the appropriate stator size. Since it comes to the stator when it is the torque of an RC motor.

Once you keep all of them in mind, you are ready to roll!


Does Torques Depend on KV?

No. The torque of the RC motor is not connected with the KV of the motor. It’s true that a higher value of KV can increase the torque constant. Torque only depends on stator size. The magnet friction of the coil affects the torque. However, the efficiency can vary a bit based on the value of KV.

What Are The Things To Keep in Mind Regarding Motor Performance?

Thrust, mass, and efficient current- these are three principal things you should keep in your head. A high thrust means larger acceleration. The heavier the motors, the more energy is required to operate them. If the current draw is efficient, then the overall performance of the drone increases.

Do The Numbers in RC Electric Motor Have Any Meaning?

Yes, it does. This number indicates the winding of the wire at the inner part of the motor. If the winding is bigger, then the motor gets slower. Meanwhile, a faster motor has a small amount of wiring. You can verify the number of the electric motor and choose the right motor.

Final Words

End of the journey, cowboy! If you have survived this far then you know about RC motor sizes. If you still have confusion, experts are always there to advise you.

I shall take leave then?

What? Even I need to check my drone’s motor size!

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