What Does Kv Mean in RC Motors?

What Does Kv Mean in RC Motors?

RC (radio-controlled) motors are among the most popular components in the world of RC vehicles. From RC cars to planes, helicopters, and boats, RC motors power the drivetrain and propel these machines to incredible speeds. One concept that newbies in the RC world often struggle with is the term “kv”. This term is used to describe the motor velocity constant or the motor’s revolutions per minute (RPM) per volt of input power applied. In other words, kv indicates how fast a motor will spin, given a certain amount of voltage or power. Kv rating is an important concept when selecting the right motor for your RC vehicle.

The kv rating is often found on the motor’s label, and can be an important factor to consider when choosing a motor for your RC vehicle. The first thing to know is that higher kv motors spin faster than lower kv ones. It is generally assumed that a motor spinning at 1000 RPM per volt at a given voltage level will spin at twice that rate when supplied with double the voltage level. Therefore, a 1000kv motor supplied with a 2-cell battery (7.4 volts) will spin at approximately 7400 RPM. However, this does not take into account the efficiency of the motor or any additional factors like the weight of the vehicle or the gear ratio. Nonetheless, the kv rating is a useful number that provides an estimate of the motor’s speed and helps in choosing the right motor for a specific RC vehicle application.

How to Choose the Right Kv Rating for Your RC Motor

Here are some factors to consider when selecting the right kv rating for your RC motor:

Vehicle Weight and Size

  • Higher kv motors work best with light or small vehicles, while low kv motors are better suited to larger and heavier vehicles.
  • Choose a kv rating that matches the weight and size of your vehicle to ensure optimal performance.

Battery Voltage and Cell Count

  • Higher voltage batteries will increase the RPM output of a motor.
  • Choose a kv rating that matches the voltage and cell count of your batteries to ensure effective power delivery.

Type of Vehicle/Intended Use

  • Higher kv motors are well-suited for high-speed performance or racing.
  • Lower kv motors offer better control and are ideal for off-road or stunt vehicles.
  • Choose a kv rating that matches your vehicle and driving style to achieve the desired performance.

When selecting the right motor for your RC vehicle, kv rating is just one of many factors to consider. Websites such as RC Universe and Horizon Hobby provide valuable resources and information on selecting and purchasing the right RC motor for your needs. Popular brands like Castle Creations, Traxxas and Team Associated offer high-performance motors with varying kv ratings to match any RC vehicle application.

How to Choose a KV Motor?

When it comes to choosing a KV motor, there are a few key factors to consider:

  • Size and weight: The size and weight of the motor will determine how much power it can output and how much space it will take up in your device or vehicle.
  • Operating voltage: The voltage of your battery or power source will determine the ideal KV rating for your motor. Higher voltage requires a lower KV rating.
  • Application: Different applications, such as drones or electric skateboards, require different KV motors. Make sure to choose a motor that is appropriate for your application.
  • Manufacturer: Look for quality manufacturers with a reputation for producing reliable and efficient motors, such as Hobbywing or T-Motor.

If you’re still not sure which KV motor to choose, there are many online forums and websites dedicated to motor selection and reviews, such as RCGroups or Banggood. Additionally, many motor manufacturers offer detailed specification sheets and customer support to help guide your decision.

Top Kv Ratings for Popular RC Motor Brands

If you’re in the market for a new RC motor, here are some of the top kv ratings for popular brands:

Castle Creations

Motor Kv Rating
Castle Creations Sidewinder 4 2S ESC w/1410-3800kv Sensored Motor 3800
Castle Creations 1515 1Y Sensored 2200kv Brushless Motor 2200
Castle Creations Mamba Monster X 3 25.2V Waterproof ESC w/1515-2200kv Sensored Motor 2200

Team Associated

  • Reedy Sonic 540-M3 Motor 7.5 Modified 1S-2S Competition Brushless Motor – 6900Kv
  • Reedy Sonic 540-M3 Motor 10.5 Modified 1S-2S Competition Brushless Motor – 3900Kv
  • Reedy Sonic 540-M3 Motor 13.5 Modified 1S-2S Competition Brushless Motor – 3200Kv


  • Velineon 3500 Brushless Motor – 10-Turn, 3500Kv
  • Velineon VXL-3s Brushless Power System – Waterproof (includes VXL-3s ESC and 3500Kv motor)

When selecting a motor, it’s important to choose a kv rating that matches your vehicle type and intended use. By doing so, you’ll be able to achieve the desired performance and speed while maintaining control and maneuverability. Online retailers such as Amazon and HobbyKing offer a wide variety of motors and kv ratings to choose from, along with customer reviews and ratings for each product.

Is a Higher KV RC Motor Better?

  • A higher KV (RPM per volt) RC motor is not necessarily better.
  • It provides faster acceleration and top speed, but sacrifices torque and battery life.
  • A lower KV motor has more torque, better battery life and is more suitable for climbing or pulling heavy loads.

If you’re looking for RC motors, websites like Horizon Hobby and HobbyKing offer a wide selection of motors to choose from. It’s important to choose the right motor based on your RC vehicle’s specifications and the purpose of its use.

Factors to Consider When Choosing a Kv Rating for Your RC Motor

Here are some factors to keep in mind when selecting a kv rating for your RC motor:

Vehicle Type and Weight

  • Lightweight/small vehicles: higher kv ratings
  • Large/heavy vehicles: lower kv ratings

Intended Use

  • Racing/high-speed performance: higher kv ratings
  • Balance between speed and control: lower kv ratings

Battery Voltage

  • Higher voltage = higher RPM output

Motor Size and Weight

  • Consider the size and weight of the motor in relation to your vehicle
  • Heavier motors may affect handling and maneuverability

Construction and Durability

  • Choose a motor that is built to withstand the demands of your vehicle and intended use
  • Look for features such as waterproofing or heat dissipation

When selecting a motor, you may also want to consider the brand and product reviews. Popular RC motor brands include Castle Creations, Team Associated, and Traxxas. Online retailers such as eBay and Tower Hobbies offer a wide range of motors and kv ratings to choose from, along with detailed product descriptions and customer reviews. Don’t hesitate to do some research and read reviews before making your final decision on an RC motor.

Is a higher Kv motor better?

  • Higher Kv (Kilovolt) motors are typically capable of faster rotation speeds than lower Kv motors.
  • However, different applications may require different Kv ratings depending on the desired performance and efficiency.
  • It’s important to consider factors such as voltage, current, and torque requirements when selecting a motor.

For more information on selecting the right motor for your specific application, check out websites such as HobbyKing or RobotShop.

The Importance of Choosing the Right Kv Rating for Your RC Motor

Choosing the right kv rating for your RC motor is a critical decision that can impact the performance and handling of your vehicle. If you choose a motor with too high or too low of a kv rating, you may find that your RC car doesn’t perform as well as you’d like. Some of the consequences of choosing the wrong kv rating for your motor include a lack of torque, reduced battery life, and overheating.

By selecting the right kv rating for your motor, you can ensure that your RC car runs smoothly and efficiently. With the right combination of speed and control, you’ll be able to enjoy the unique thrill of driving a radio-controlled vehicle to its fullest potential.

So whether you’re new to the world of RC vehicles or a seasoned pro, take the time to consider your options carefully before selecting a kv rating for your motor. Do your research and consult with other hobbyists, and don’t be afraid to experiment to find the perfect combination of motor and kv rating for your particular vehicle and driving style. With a little bit of trial and error, you’ll be on your way to dominating the track or the backyard with your high-performance RC car.