Electric motors are essentially the heart of EVs and electric bikes without which the EV revolution wouldn’t have been possible. Ebikes generally don’t get the same hype as electric cars but they also utilize very advanced battery & motor technology. The use of sophisticated technology and different types of ebike motors have, in fact, increased the versatility & acceptance of electric bikes which is a great thing, especially for our urban environment.
Ebike motors may look similar from a distance but not all of them are based on the same working principle. Detailed below are the different types of ebike motors and their operation which, in turn, will help you make the best buying decision when looking for an electric bike.
Geared Hub Motor:
Geared hub ebike motors are based on a system of a number of small gears which then ultimately drive the wheel. The almost-direct power delivery system and many other unique properties of an ebike hub motor provide several advantages & disadvantages that are discussed below.
Pros & Cons:
Smaller, affordable & lighter than its competitors
More durable because of its “internal gears”
Direct power delivery system reduces power losses and wear & tear
No room for power amplification since these motors don’t drive the crank
Impressive low-end torque
Average higher-end torque & speed
Great for off-roading & heavy-duty purposes, also ideal to be used in smaller bikes
Not as efficient as its competitors, and it is hard to remove the rear wheel because of the extra effort required to deal with the motor
Direct Drive Motor:
Direct drive motors, as the name implies, are directly connected to the rear wheel's hub, and thus provide instant feedback. Instead of employing several small gears, a direct drive motor utilizes a system of rare earth magnets that provides some unique benefits which make direct-drive motors one of the best ebike motors available out there. However, just like a geared hub motor, a direct drive motor too has some disadvantages that are discussed together with its advantages below.
Pros & Cons:
Provides better high-end torque
Larger in size & heavier in weight than geared hub motors
Supports regenerative braking which recoups some of the lost energy
Despite being efficient on longer routes, their range is relatively lesser
Quite silent in its operation
The motor takes the direct toll of wear & tear
Most widely used in ebikes
Makes removing the rear tire somewhat difficult
Image credit: Velorution
Mid Drive Motor:
The Mid-drive motor is different from the rest of the two motors in the sense it is located in between the pedals and the power is delivered to the rear wheel by the chain. Its central position makes it unique and better than others in some ways but there are some downsides too.
Offers the best performance
Considerably pricier than the other two options
The center placement offers the best weight distribution
The center placement increases stress on the chain, thus, requiring frequent replacement
Lighter in weight, ideal for high-end bikes
The rear wheel is easily removable due to the absence of a motor in its center
Chain breakage will make the bike undrivable
Motor power is multiplied as a result of power delivery through the chain, which results in better output than one expects
Noisier than hub motors
Mid Drive vs Hub Motors:
Mid-drive motors are generally regarded as the best ebike motors out there, but they are limited by their steep price tag. Their centered position allows a more balanced ride, on the other hand, hub motors naturally aren't as balanced as mid drives. On the plus side, hub motors are affordable both in the short & long run because of their low price and maintenance.
Performance is one of the main aspects of any ebike motor, and this is where mid-drive ebike motors take a clear lead. They provide better lower and higher-end torque leading to the emission of lesser waste heat energy that ultimately enhances the lifespan of a mid-drive motor. On the contrary, it is an opposite case for hub motors, but their attractive price makes them a favorite for many ebike companies & consumers alike.
Direct Drive Hub Motors vs Geared Hub Motors:
Direct drive and geared hub motors are often confused as the same types because of their placement but they have significant differences that make them distinct from one another. Ebike hub motors are great for low-end torque whereas direct drive ebike motors are best for high-end torque meaning they perform best at high speeds.
Since the direct drive motor itself drives the wheel, therefore, it has to be large enough to generate ample output to push the wheel. A large size translates into heavier weight which is a major negative of direct drive motors that isn’t present in geared hub motors.
Generally speaking, direct-drive motors are quieter in their operation when compared to ebike hub motors. Whether you are speeding down the road or are just coasting to recoup the lost energy, direct-drive ebike motors will provide you the most serene ride you'll ever experience from an ebike.
What Does Power Rating Mean to Electric Bikes?
Power ratings are a measure of rating an electric bike’s motor’s power output and it should never be confused with the actual power output. Generally, ebike motors are stamped with the maximum power rating, and there is no set amount of time for which the peak power may actually last. Most mainstream electric bikes are rated between 250 watts and 750 watts, but this rating does not take into account the wasted heat energy. The efficiency rating and the torque figure provide a better estimate of the usable energy therefore they should also be considered if the aim is to know the accurate capability of an ebike.
For more information about Ebike, feel free to check Sdream.Bike website