Get ready to reach the stars with a new set of FPVCrate V2 Booster Motors!

In This Month’s Crate:

• 4 X Booster V2 Motors (4s or 6s)
• HQ Prop R35 Freestyle Propellers (3 Sets)
• Freedom of Flight T-Shirt
• 2 X ZOHD Battery Straps
• FPVCrate April Sticker Sheet
• Discount Coupon Card

Let’s take a deeper look at this month’s premium item, the Booster V2 Motors:

• Model - Booster, V2
• Motor Size - 2207
• KV Rating - 2700 Kv (4s), 1900 (6s)
• Motor Base - Naked
• Shaft - Clockwise 
• LiPo Cell Rating - 4s-2700Kv,  6s-1900Kv
• Wire Size - 20 AWG

This month we'll focus on brushless motors. What is a brushless motor? What do the specs mean? How do I wire them up? Keep reading to find answers to these questions and more.

Brushed and Brushless Motors

In our hobby, we will run into two styles of electric motors - brushed and brushless. Generally, we will only see brushed motors in the sub-micro Tiny Whoop style builds, whereas most larger builds will use brushless motors.

Brushed Motors

Brushed motors are the original electric motor. They get their name from the soft, stationary electrical contacts, called “brushes”. These brushes transfer the electrical current from the battery to the rotary switch (commutator) on the shaft of the motor. This, in turn, supplies current to the motor windings, which creates the magnetic field that creates torque (movement) and spins the motor. 

There are several disadvantages to brushed motors. The friction of the brushes robs power and performance from the motor. This also causes wear and requires earlier replacement of the motor. The direct contact of the brushes can also cause excessive sparking (power loss and fire hazard). These problems were eliminated with the invention of the brushless motor.

Brushless Motors

Brushless motors were created by replacing the physical bushes with electronics (thank you semiconductor revolution!) which eliminated the friction and power loss of brushed motors. This means motors with more torque and a higher thrust to weight ratio. The elimination of the brushes also creates a motor that lasts much longer, and creates far less electromagnetic interference, which makes all of our other on-board electronics VERY happy! 

Our standard hobby motors have permanent magnets glued into the bell housing (the rotating outer part of the motor). The bell housing rotates around the fixed armature and is controlled by the electronic speed control. 

Brushless Motor Specs - What Do They Mean?

Motor Size

Brushless motor size is represented with 4 numbers. These 4 digits are the dimensions of the motor’s stator (the bottom part of the motor that holds the wire windings). FPVCrate Boosters are 2207 motors. The first two digits are the motor’s stator diameter, the second two digits are the motor’s stator height. FPVCrate Boosters have stators that are 22mm in diameter and 7mm tall.

Kv Rating

Kv rating for brushless motors is the revolutions per minute (K) of the motor per volt (v) applied to the motor, with no load (no prop) on the motor. Knowing the Kv of the motor and the size and pitch of the props is important to avoid overheating and damaging the motors/ESCs. By varying the motor Kv, battery cell count (voltage), and prop size/pitch you can get the optimum performance from the craft you are flying.

FPVCrate Booster motors come in two Kv varieties:

• 2700Kv - Higher Kv motors (high speed, low torque) are better suited for 4s batteries
• 1900Kv - Lower Kv motors (low speed, high torque) are better suited for 6s batteries 

Wiring up Brushless Motors

Brushless motors have three wires that exit the armature. These wires are soldered to the three solder pads on an electronic speed controller (ESC). The direction the motor will spin depends on what order the motor wires are soldered to the ESC. Testing your motors (WITHOUT PROPS!!!) through the Betaflight Configurator will let you know if your motors are spinning in the right direction. If any of your motors are not spinning in the right direction, there are two methods of reversing individual motor directions:

1. Switch the position of any two motor wires on the ESC. By resoldering the wires on different pads it will switch the direction of rotation.
2. By connecting to your ESCs through BLHeliSuite (be sure to use the right version for your computer/operating system/ESC style) and reversing the motor direction for the appropriate motor.

Be sure to test your motor direction again after making the changes, and then you are ready to RIP!