E-bike Motors Explained

A big part of the decision about what e-bike to buy is learning about its motor because the e-bike’s motor is one of the bike’s most important components. In this article we will discuss the types of e-bike motors and their features...and how the motor will affect your e-bike. Let's dive in.

If you’re charged up to get on an e-bike because a.) you want to spend less time in traffic; b.) there are far more adventures to be had beyond your current limits; c.) getting around by e-bike is simply cleaner and greener; or d.) all of the above, then you’ve got lots of options. 

Let’s begin with  what an e-bike is, which is basically a pedal bicycle that’s assisted by a battery-powered motor. Next up is to decide if you want an e-bike for commuting, trekking, mountain biking, road riding, or hauling cargo. Part of this decision is learning about what kind of motor you want.

What is an electric bicycle motor? 

An e-bike motor provides you with electric assistance to reduce the amount of pedaling power needed to power your bicycle’s forward momentum. This enables you to climb hills more easily, reach higher speeds with less physical exertion, and endure longer rides than if you were riding a traditional bike. 

It’s important to point out that e-bike motors are typically restricted to 25 kilometers per hour, depending on government regulations.

What are the main types of e-bike motors?

E-bike motors fall into two categories: hub motors or mid-drive motors. 

• A hub motor is mounted in the front or rear wheel and either “pulls” or “pushes” the bike and rider. 

Did you know?
Some standalone hub motors can convert a favorite traditional bike into an e-bike, which can be a relatively economical solution, however widespread demand for e-bikes has resulted in more sophisticated, purpose-built bikes at competitive prices. 

• A mid-drive motor is integrated with the drivetrain and is installed directly onto a frame that’s been designed around the motor, like this one:

Hub-drive vs. mid-drive motors. Advantages and disadvantages. 

Here’s where you get to ask yourself some probing questions, starting with “which motor will best suit my needs?” Where you ride and what your demands are for your e-bike will help define what kind of e-bike motor you need. For example, you may have to carry your e-bike upstairs to store it, you are planning to haul heavy loads, or your budget for purchasing an e-bike has a limit*. To make this decision a little easier, below we’ve listed some of the pros and cons to each type of e-bike motor.

*In an effort to reduce a dependence on cars, some national governments even subsidize e-bike purchases. 

Hub motors

Hub motors offer some advantages that mid-drive motors can’t compete with. Lighter weight, easy for manufacturers to adapt to a bike wheel, and some almost as powerful as mid-drive motors, here are some of the advantages to hub motors:

• Rear hub motors most closely resemble the sensation of riding a traditional bike because the power runs to the rear wheel. This also reduces or eliminates any chance of the rear wheel spinning out thanks to the weighted backend. 
• Front hub motors offer extra traction thanks to the all-wheel drive system created by powering both wheels independently.
• Of the three motor mounting options (front, rear, mid), front hub motors are the easiest to install and remove because there’s no gear system to interfere with when repairing a puncture.
• Sensors used to manage electric assistance are more intuitive in rear hub motors.
• Rear hub motors also offer a wider range of power options because frames designed for rear hub motors can handle them.

It’s important to point out that rear hub motors provide a ride sensation that’s similar to riding a traditional bike but with a high power output and superior power delivery. Except for theBandit andAdventure e-bikes, all other Econic One models have rear hub motors by Bafang. Hub motors aren’t without their disadvantages however, but again, it’s worth it to fine tune what you need in an e-bike to help you decide which would be better for you: a hub or a mid-drive motor. These disadvantages to hub motors may sway your opinion in the opposite direction to choosing this option:

• Low power options are most common for front hub motors, which make them less than ideal for hauling large loads or climbing long, steep hills.
• Because there’s less weight over the front wheel, there’s a higher tendency to spin out on loose or steep terrain. Of course, you can compensate by shifting your weight forward on unpredictable terrain, which is a cheap hack for stabilizing traction.
• On the other hand, if both the motor and battery are mounted in the rear, the weight imbalance can make the bike hard to handle (and lift if it needs to be carried upstairs).
• The sensors that control levels of electric assistance in a front hub motor are more like presets rather than the reactive, intuitive sensors found on other e-bikes.

Mid-drive motors

Most often found on e-mountain bikes (e-mtb’s), these motors allow bike manufacturers to design frames that closely resemble their human-powered versions, thanks to the motor’s compact size. E-bike motors in general seem to be forever on a weight loss program and have yielded great results for mid-drive motors, which have allowed bike designers to tweak frame geometry even more to resemble riding a traditional bike. Econic One has chosen Bafang mid-drive motors for its solid reputation for manufacturing complete e-drive systems and for their proven advantages, like these:

• By positioning the motor low and in the bike’s center, the rider gains a lower center of gravity, which makes the bike easier to ride and – if need be – to carry.
• The motor’s position also doesn’t affect the bike’s suspension (too much), thus making them ideal for riding off-road.
• With the motor and pedals directly connected, power gets transferred directly from the rider.
• In the unfortunate event of a puncture, both wheels can be easily removed because they are not connected to the “e” part of the bike.

Early versions of mid-drive bikes didn’t earn a lot of fans because they were heavy, the transition between pedaling and electric assistance wasn’t that smooth, and because components like chains, chainrings, and cassettes weren’t yet built to handle the increased demands of mid-drive motors. These disadvantages have mostly been sorted out since those early days but there are still some things to consider with mid-drive motors, for instance:

• Service can usually only be performed by an authorized mechanic or retailer, or the motor must be sent back to the manufacturer for servicing. This can keep you off your bike for a while.
• Some manufacturers persist in using components that aren’t dedicated e-bike components, which means they can wear out faster and even fail more frequently.

What is the best e-bike motor for you?

The best practice is to choose an e-bike based on your preferences and ride environment and not based solely on the motor (same as you wouldn’t choose a traditional bike based on the crankset). That said, key features to look for include power, maximum torque, and – to a lesser extent – weight.

Power in wattage is a measurement of how much power the electric motor can potentially generate. 250-watt motors are among the most common e-bike motors to serve a variety of purposes. More wattage of course means more power, which is handy if not necessary for steep climbs and big loads but there is a point at which too much power is illegal. That power maximum varies by government, so it helps to be informed before throwing your leg over your e-bike.

Torqueaffects how power is delivered to the rear wheel and it’s up to you to decide how to use that power. For example, an easy power setting may only deliver 50 percent electric assistance and you will have to make up the difference, which is where torque matters. Econic One bikes with mid-drive motors have amaximum torque of 80 N-m while its rear hub motors have a maximum torque of45 N-m.

Weight is worth mentioning because it will affect the maneuverability of your bike although once you get used to handling your e-bike, weight becomes less of an issue with electric assistance. Where the motor is mounted on the bike will also affect bike handling but the motor’s weight won’t dramatically change that. Most motors tip the scale somewhere between 3.2 and 4 kilograms but there are some who defy this margin and weigh less (and more) depending upon where they are mounted and what they are used for.

E-bike motors are literally accelerating the explosive e-bike trend and helping to get more people to take up riding for health, humanity, and the planet. You may have a more practical reason for getting on an e-bike and no doubt, there’s one out there that’s precisely what you’re looking for (have you lookedhere?).  The motor is the star component (and the most expensive one) so it’s wise to know their benefits and their limits (most of which are imposed by government regulations) – just don’t let those limits stop you from going beyond yours.

by Wendy Booher