When looking at purchasing an electric motorcycle, there are a wide variety of options to choose from. One such option is having a brushless motor. What does that mean and why is that an advantage?
A brushless motor is a way to power the armature of an electric motor by changing electromagnetic poles without the use of a brush within the motor. It’s done instead by switching the position of the components that create the electromagnetic field that powers the spinning of the armature that drives the motor.
That sounds complicated, doesn’t it? Well, let’s start first by describing, in general terms, how an electric motor works.
The rough outline of how an electric motor works is as follows:
- When electricity is allowed to flow into an electric motor (which is DC instead of our standard AC power source), it goes into an internal component called an armature.
- The armature contains an electromagnet that will activate the magnet when electricity is introduced.
- There are magnets on the outside of the DC motor called the stator that are fixed in place.
- The magnetic field created by the armature will spin 180 degrees inside the motor due to the reaction it is having to the magnets in the stator.
- To keep the armature spinning, you have to change the magnetic poles continuously.
- This change in polarity is what brushes are used for.
- Brushes in an electric engine will contact two spinning electrodes that are connected to the armature.
- This contact by the brushes will flip the magnetic polarity and propel the armature to push it 360 degrees over and over.
- That is somewhat similar to how pistons turn the crankshaft on an internal combustion engine to power the crankshaft.
Why Is Having a Brush Motor A Bad Thing?
Well, technically, it’s not. There are many motorcycles (and other electric vehicles) that use brushes in their motors to great efficacy. However, there are some disadvantages to having brushes:
- The efficiency of a brush motor is about 75%-80% versus a brushless motor which is 85%-90% efficient. That translates into a longer riding range and longer battery life.
- Brushes wear out and have to be replaced
- Even less mechanical noise coming from an electric motor than usual
- Heat buildup can be an issue with brushes. A brushless motor is far more capable of dissipating heat.
If you have a choice between getting an electric motorcycle with a brushless motor versus one with brushes, go with the former. It’s better for your motorcycle long-term and it’s a far better investment.