Table of Contents

Guide to Electric Bike Motors | Types, Brands and Tips

Bosch electric bike motors

Table of Contents

An electric bike motor is your best friend when riding an e-bike. It’s the helping hand that boosts you up the hills, takes the pressure off your legs and makes riding a heck of a lot easier.


It’s one of the main reasons why e-bikes and e-MTBs cost that little bit more and why getting the right set-up for your needs is so important.


In this guide, we’ll delve into e-bike motors and look at the different types available, the brands which nail electric bike motors, and some practical tips to help you on your way.


Right, then, let’s get stuck in!

What Does an e-Bike Motor Do?

E-bike motors give the bike the electrical assistance you need to go that little bit quicker, help you up the hills and get you up and over obstacles. The motors are pedal-assisted, so when you turn the pedals and have the electrical assistance switched on, you get a boost.


If the battery stores the electrical power, the motor actually makes that power work to create torque, which is what propels you forward. Torque is measured in Newton Metres (Nm), and most electric bikes on the market will reach a maximum of 25km/h (15.5mph) with electrical assistance.


Electric motors for bicycles come in a variety of Watt sizes, with a usual maximum of around 250Wh

The Different Types of e-Bike Motors

There are several different types of e-bike motors, and the differences lie in where they’re positioned on the e-bike or e-MTB. All offer something ever so slightly different and have their own pros and cons.


These include hub drive motors, crank drive motors and geared hub motors.

Gearless Hub Drive Motors

gearless hub drive motors

Gearless hub drive motors, also known as “direct-drive” motors, are situated inside the wheel itself. By being based inside the wheel, the motor directly makes the wheel turn. These are quite large motors, and with that size comes quite a bit of extra weight.


These are usually cheaper than other e-bike motor options, but as a result, can be less powerful and only come with one speed of assistance. Hub drive motors are often found on city rental and daily commute e-bikes, where things like weight and power are typically less important.


If the battery dies, then you’ll end up feeling a lot of resistance, which is clearly problematic and they become cumbersome on longer rides. These motors aren’t suitable for e-mountain bikes; these require motors that are lighter and have a bigger boost to get you up steep inclines.



Geared Hub Motors

geared hub drive motors

Geared hub motors work in a similar way to gearless hub motors, with the motor based inside the wheel. They’re more advanced than a gearless hub motor, though, and offer various speed options.


These motors are smaller and lighter than a gearless hub motor and allow you to coast on the pedals without resistance. Geared hub motors are better on the hills than a gearless hub motor and can generate a greater amount of torque.



Crank Drive Motors

crank drive motors

A crank drive motor, also known as a mid-drive motor, is based around the pedal cranks and generates the power directly through the bike’s chain. These are much more powerful than the previous two options, are usually geared, and are very good for getting up steep hills.


Crank drive motors are often found on e-MTBs because, not only are they more powerful, but they also have a better centre-of-gravity, which is important for manipulating a bike on those tricky trails. Overall, handling is much better with a crank drive motor and they’re usually much lighter.


They’re much more advanced, tech-wise, and work in tandem with the battery to conserve power when assistance isn’t needed. Because the crank-drive motor isn’t situated in the middle of the wheel, it makes fixing punctures much easier, too.


As you can see, they offer quite a lot more than a hub drive motor, but with that comes extra cost.



Best Brands for Electric Bike Motors

So, we’ve now highlighted the different types of e-bike motor, but who are the main players in the e-bike motor market?


Shimano, Bosch, Specialized and Yamaha are among the most proficient at creating top-quality e-bike motors, but what do they each offer and how do they differ?


In this section, we’ll have a proper look at why these brands stand out in the field.

Bosch e-Bike Motors

Bosch is incredibly well-versed on making solid e-bike motors and they’re the most commonly used in the e-bike market. Its motors are amongst the most powerful and efficient out there, whilst also being very reliable.


The Bosch range covers a variety of riding styles, including city riding and motors designed for the e-MTB market.

Active Line & Active Line Plus

Good for: daily commuting, city spinning.

Bosch ActiveLine bike motor



Bosch Performance Line CX

Good for: e-MTB riding.

Bosch PerformanceLine CX bike motor



Electric Bike Shimano Motors

Shimano has cemented itself as a serious player in the e-bike motor market, producing fantastic crank drive motors. As a company, Shimano produces a range of different e-bike motors for a variety of different riding styles. What’s noticeable about Shimano’s motors is their compact size and reliability.

Shimano E5000 and E6000

Good for: city spinning, daily commutes, longer distance bike-packing.

Shimano E6000



Shimano E7000, E8000 & EP8

Good for: e-MTBs.

Shimano EP8



Yamaha e-Bike Motors

Yamaha is another decent player in the e-bike motor market. The company has one core model, the PW-X, which is one of the best out there for e-MTBs. It provides a powerful kick and is your best friend on those steep mountain trails.

Yamaha PW-X

Yamaha PW-X

Good for: e-MTBs.



Specialized Electric Bike Motors

Specialized offers some of the most powerful crank drive motors out there, and is definitely amongst the best motor manufacturers in the e-MTB market. The company offers two core products that provide differing levels of turbo assistance, depending on your needs, but both are excellent options.

Turbo Brose

Good for: long off-road rides, bike packing, and general trail.

Turbo Brose



Specialized Turbo SL

Good for: challenging mountain bike trails, enduro.

specialized turbo sl



Best Hub Drive Motor Brands

When wondering how you choose an e-bike motor? It’s important to think about the type of riding you’ll largely be doing, as this will ultimately determine which is right for you.


There’s less competition in the hub drive motor market, because hub drive e-bikes aren’t geared up for top-level riding, challenging conditions and e-MTBs.


Hub drive motors are typically found on standard commuter e-bikes and the types you might find in cities to rent. The best ones out there include:

  • Mahle EbikeMotion
  • SR Suntour
  • Giant SyncDrive
Mahle EbikeMotion
Giant SyncDrive

All 3 of these emit much less power than the crank drive motors we mentioned in this article but offer the best weight-to-power ratio.



Practical Electric Bike Motor Tips

Electric Bike Motor Troubleshooting

Problems with your e-bike motor is one of the main causes of many issues with an e-bike or e-mountain bike. Your first port of call should be to check your motor if you have a problem with your electrical assistance.

Important to note:

  • Playing around too much with an e-bike motor, particularly taking it apart, can void warranties (depending on your purchase date). So, make sure you really know what you’re doing before taking anything apart or opening the motor up. It might be best to take it into your local bike shop.

Common Issues with e-Bike Motors

Motor Controller Problems:

The motor controller is what switches your electrical assistance on and off. Issues with a motor controller will force the electrical assistance to switch off suddenly or not start in the first place.


Connections between the controller and the motor can become weakened, particularly due to big impacts.


Switch the power off and on at the controller end. If it fails to power up properly, or is jerky, then you have a problem with the controller that needs looking at.


Checking the on/off function regularly is good practice to keep an eye on your e-bike motor health.

Wiring Issues:

This is one of the main issues with e-bike motors.


Bouncing around on the challenging trails can cause wires to loosen, break or disconnect from their hubs.


Mud, twigs and other debris can also damage the wiring. So, if the motor isn’t working, check whether anything is loose or anything is blocking the wiring’s path.


Keeping your bike clean and well-maintained can help keep track of any debris.


Overuse of the electrical power assist, particularly on big inclines, can also cause the motor to overheat, which can also cause the wires to melt. If you can smell a plastic burning smell, then it’s likely you have an overheating issue.


In cases where there is a loose wire or melted wire, it’s best to go into your local bike shop to get it fixed. Wiring issues are particularly common in rear-hub motors.

Final Thoughts

When choosing what size of motor you need for your e-bike it’s important to consider the type of riding you’ll be doing. If it’s daily commuting, general riding and longer-distance pedals, then it’s likely that a hub motor will suit your needs best.


Meanwhile, if you want to hit the trails, go up steep inclines, and have efficiency and greater handling, then a more lightweight and powerful crank drive motor is best for you.


Keeping on top of electric bike motor maintenance is very important too; otherwise, you could encounter problems with the most important aspect of your e-bike.


The motor, along with the battery, is what you pay a premium for with e-bikes and why they cost more than their non-power-assisted counterparts.


There are some cracking e-bike motors on the market and both the size, efficiency and power levels are regularly evolving, with the technology constantly improving.


Now, get out there and find out for yourself what all the fuss is about!