Electric Bike Conversion Kit – Brushed vs Brushless Motors

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Updated September 16, 2022

If you are looking for an electric bike conversion kit with an electronic controller and an electric motor to turn your standard bike into an e-bike, you may be comparing electric bike conversion kits with brushed vs brushless motors. The best electric bikes and conversion kits, after all, tend to include one of these types of motors. Here are the differences between the two

KEY TAKEAWAYS:

  • When it comes to the motor designs found with e-bike conversion kits, you have brushed DC motors and brushless DC motors to choose from.
  • Brushless motors are more durable and long-lasting, as there are fewer points of contact between sensitive components.
  • Brushless motors also allow for higher maximum speeds, though they are more expensive.

Differences Between Brushed and Brushless Motors

When it comes to the motor types typically found in electric bikes and conversion kits alike, they fall into one of two categories. Brushed DC motors use a configuration of wound wire coil to interact with electromagnets and the motor itself. The coil does not rotate, but the brushes come into contact with the electromagnetic regularly, which are the primary differences from a brushed DC motor.

Brushed DC motors, otherwise known as BLDC motors, use a permanent magnet to reach a similar result as a brushless motor. The coil rotates to meet this magnet, but there is no physical contact otherwise. This leads to a number of performance differences, which are slightly in line with when you compare direct drive vs a geared motor with electric bikes.

Insider Tip

Electric bike conversion kits will save you money over a pre-manufactured e-bike, but the installation process may be lengthy.

Durability

Brushed DC hub motors are generally thought to be more durable and long-lasting than brushed hub motors. Why? There is not much physical contact between the components, so they tend to stay in tip-top shape for longer. Brushless hub motors, on the other hand, feature brushes that constantly come into contact with the motor coil and other components. This leads to a degradation of these components, particularly the brushes themselves. In other words, you will have to get these brushes replaced regularly as a part of your overall maintenance routine.

Speed

Generally speaking, brushless motors allow for higher maximum speeds than brushed DC motors. This all boils down to energy efficiency. Brushless motors are highly efficient (85-90%) compared to brushed motors (75-80%). This increased efficiency also translates to battery life, which is important if you are comparing electric bike batteries of 36v and 12ah vs 48v 9ah. Additionally, you will want an efficient motor if you live in a hilly area. You will also want to have one of the top-rated e-bikes for hils.

Cost

Brushless motors will tend to cost more than brushed motor designs, which will translate to the cost of the e-bike or conversion kit itself. An important factor if you are using a conversion kit is what type of moor to use, each type has there advantages and disadvantages. You can learn more about these motors by reading about electric bike mid drive vs wheel hub. Also, depending on the suspension your bike has, you may need to know how to put an electric motor on a rear suspension bike if you’re using a conversion kit. However, if you haven’t decided on going the electric route yet, you can check out our comparison of e-bikes vs mountain bikes to help you out.

F.A.Q.S

Are e-bike conversion kits worth it?

These kits include an electric motor, a rotary switch, and motor controllers, along with a lithium battery pack. They allow you to turn a pre-existing bike into an e-bike, thus saving on costs. For some, they are worth it.


Are e-bike conversion kits legal?

These bikes are legal, assuming the motor does not go faster than legally allowed. If you have a high-powered motor with plenty of motor power, you may need a license and insurance.


What does it take to install an e-bike kit?

You will need a bike to install the kit on and a variety of tools. Check the instructions for details.



STAT: A University of Tennessee study provides evidence that energy expenditure (EE) and oxygen consumption (VO2) for e-bikes are 24% lower than that for conventional bicycles, and 64% lower than for walking. (source)

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