Compare Hub vs Mid-Drive Motors for Electric Bikes Advantages & Disadvantages…

Compare Hub vs Mid-Drive Motors for Electric Bikes. Advantages Disadvantages

E-bikes are a great way to get around and can provide a fun and efficient way to explore your surroundings, but with so many different models and options available, it can be difficult to know which one to choose.

And, one of the most important decisions to make when choosing an electric bike is the type of motor the bike uses. This is because your riding quality, price, and performance of the bike greatly depend on the motor.

In that case, with two main types of electric bike motors which are hub motor and mid-drive motor, how do you choose?

To help you have a better understanding of both the motor powered bike, we’ll explore the differences between hub motors and mid-drive motors along with their pros and cons, so that you can make an informed decision when choosing the motor for your next electric bike.

What Is A Hub Motor Electric Bike?

Electric hub bike motors are usually integrated into the front or rear wheels. Simply put, it is an electric motor that is built into the hub of the wheel.

The hub motor is powered by a battery that is located on the frame of the bike. This type of e-bike is designed so that the motor provides power directly to the wheel, propelling the bike forward. Another thing is not affected by gear changes.

These types of motors are easier to install, and it is also more affordable than mid-drive motors.

Generally, there are two types of hub motors, for example, geared and gearless hub motors. They are popular for their simplicity and ease of use, as the motor is hidden from view and does not interfere with the look or feel of the bike.

Advantages of Electric Bicycle Hub Motor

  • The biggest advantage of a hub motor electric bike is its easy installation and maintenance.
  • The hub motor is usually much lighter than a mid-drive motor, which makes it easier to maneuver and transport.
  • Due to its enclosed nature, this system has much less potential to fail.
  • Avoid over-stressing your chain or shifters and causing parts to wear out faster.
  • Quiet operation.
  • Good for casual riding.
  • Can be used with any type of bike frame.
  • affordable than mid-drive motors.

Disadvantages of Electric Bicycle Hub Motor

  • Heavier than mid-drives
  • Lack of torque for climbing hills
  • Reduced efficiency in high gear
  • Limited options for customization
  • Lower performance compared to mid-drive motors
  • Tire changing is more difficult with hub motors

What Is A Mid Drive Ebike?

A mid-drive electric bike is a bike that uses a mid-drive motor in its drivetrain. It is located in the middle of the bike between the pedals, and it is powered by a battery that is also located in the middle of the bike.

The mid-drive motor is connected to the crank, which allows it to use the bike’s gears to provide more power and torque which results in providing more control and efficiency. This motor is usually known as being more powerful and efficient than a hub motor, and it is also more responsive.

Additionally, mid-drive motors are popular for their improved performance, especially when climbing hills and negotiating rough terrain.

Rather than powering the wheel directly like hub motors, mid-drive motors provide power to the bike through its drivetrain. The motor attaches to the cranks and chainring, and its power is then transmitted to the rear wheel via the chain.

Advantages of Electric Bicycle Mid-Motor

  • Better ridge quality and more range.
  • Offers 10 to 15 miles more range than the hub motor model.
  • Improved torque for climbing hills.
  • Better control and stability on rough terrain.
  • Increased efficiency in high gear.
  • customizable with different components.
  • Smaller and lighter than a hub motor of similar power.
  • Freedom to use any wheels, tires, and cassettes that you wish.

Disadvantages of Electric Bicycle Mid-Motor

  • complicated installation and maintenance.
  • Can output 250-750 W of power continuously.
  • expensive than hub motors.
  • Heavier motor weight.
  • Limited options for frame compatibility.
  • noise during operation.

What Is The Difference Between A Mid Drive And Hub Motor Ebike?

When it comes down to buying an electric bike, apart from the motor, there are some other common things to consider, such as range, riding quality, reliability, safety, etc.

So, here we will discuss how the differences between these two hubs and mid-motors affect other factors of an electric bike.

Range

Mid-drive motors tend to have a longer range compared to hub motors because they use the bike’s gears to transfer power, resulting in more efficient use of energy. The mid-drive motors can also make better use of the energy generated by regenerative braking, which helps to extend the range of the e-bike.

Hub motors, on the other hand, can have a shorter range because the motor is located in the wheel, which can cause a loss of energy through friction.

Where from a mid-drive ebike you may get over 40 – 45 miles of range, a hub drive motor only offers 25 – 30 miles of range. This means a mid-drive motor is more efficient than a hub motor and can provide a longer range.

Of course, you can get an increased range with a hub drive e-bike also by installing a large capacity battery. For example, the Himiway cruiser ebike that comes with a geared hub motor with a 48V 17.5Ah battery. And, despite being a hub-drive e-bike, it is known as the long range electric fat tire bike that offers a 35. 60 miles range per charge.

compare, mid-drive, motors, electric, bikes, advantages

Handling

To ensure optimal handling of an e-bike, the weight should be balanced between the front and rear axles.

In that case, with a mid-drive e-bike, the motor and battery are situated in the center of the frame, so the additional weight is spread evenly between the front and rear of the bike.

Additionally, a mid-drive motor is connected to the crank, which allows it to use the bike’s gears to provide more power and torque. This results in improved handling and stability, making the bike easier to control.

Hub motors, on the other hand, tend to have a heavier weight distribution and the motor’s weight shifts the bike’s center of gravity either forward or backward, which can negatively impact handling, especially when riding on rough terrain.

This means, in terms of handling, mid-drive e-bikes are better than hub-drive e-bikes.

Ride Quality

A mid-drive motor is more responsive than a hub motor, so it can provide a smoother ride.

Mid-drive motors tend to offer a smoother ride because they use the bike’s gears to transfer power. This allows for a more gradual distribution of power, resulting in a smoother ride.

Conversely, hub motors will give you a feel like you are being pushed because the motor provides direct power to the wheel, which can result in a jarring and rougher ride experience.

Gears

The biggest advantage of a mid-drive ebike over a hub-drive e-bike is that mid-drive motors make better use of the bike’s gears, which helps to increase efficiency and improve performance.

Being able to change the gears, you can keep the electric bike’s motor running at its optimal RPM. This results in using less electricity, improving your range, and producing more power and torque while riding.

But, in the case of hub motors, it can’t utilize the bike’s gears as the motors of hub-driven e-bikes operate independently from the drivetrain. This means hub motors may run outside their optimal RPM, the motor will run slow while climbing hills, burn more energy, can’t supply power as much, and ultimately can limit performance.

So, in terms of gears, a mid-drive motor is connected to the crank, so it can use the bike’s gears to provide more power and torque.

Motor Size And Weight

If you are a cyclist, you must know that the lighter your electric bike the faster it will be. Not only this but a lighter e-bike is much more efficient and easier to maneuver also.

So, when it comes to motor size and weight, hub-drive motors tend to be larger and heavier than mid-motors, which can impact the weight and balance of the bike.

On the other side, mid motors are typically smaller and lighter and are really easy to carry and ride.

Climbing Hills

Mid-drive motors offer improved performance when climbing hills, due to their increased torque and the ability to make better use of the bike’s gears.

With a mid-drive e-bike when encountering a steep hill, you can shift down to reduce the gear ratio. This takes less force to spin the cranks.

Additionally, with a lower gear, the motor won’t have to work as hard, while still keeping a high RPM. This is beneficial as electric motors usually perform best when running at high RPMs.

In contrast, hub motors tend to struggle when climbing hills, as they have lower torque and lack gear options.

This means, a mid-drive motor is more powerful than a hub motor, so it can provide more power when climbing hills.

Reliability

Hub-drive motors can be more reliable and safer compared to mid motors because they tend to last longer than mid-drive motors. In fact, as it doesn’t have any gear inside, there is no fear of wear out or break.

Another benefit of a hub motor is that it will give you redundancy as the motor works independently from the drive system. This means if your bike’s chain breaks, you can still ride the bike by pedaling.

Mid motors, on the other hand, have more complex electronics and gear reduction and do not offer redundancy which can increase the risk of failure, malfunction, and reliability.

So, it’s evident that a hub-drive motor is more reliable and safer than a mid-motor.

Regenerative Braking

Hub-drive motors can make better use of the energy generated by regenerative braking, which helps to extend the range of the e-bike. Mid motors, on the other hand, do not make use of regenerative braking since the motor does not rotate while the rider is not pedaling, thus resulting in a shorter range for the e-bike.

In short, a hub-drive motor can provide regenerative braking, which allows the battery to be recharged while braking.

Performance

Mid-drive motors are known for their better performance on challenging terrains, like steep hills and rough trails. This is because the motor is located close to the bike’s center of gravity which results in improved weight distribution and enhanced capability to navigate difficult terrain.

Mid-drive motors are also known for providing better torque, power through the drivetrain, acceleration, reaching a higher top speed, and climbing better making them a better option for more demanding riders.

On the other hand, hub motor e bikes can be less stable on rough terrain because the motor is located in the wheel, which can affect the bike’s balance.

All in all a mid-drive motor is more powerful and efficient than a hub motor, so it can provide better performance.

Throttle Control

The way that an electric bike is powered can impact throttle control. Hub motor ebikes typically use a throttle to control the amount of power the motor provides, while mid-drive motors use the pedal assisted bike motor, which provides power when the rider pedals the bike.

Some riders prefer the throttle control offered by hub motor ebikes because it is more intuitive, while others prefer the natural feel of pedal assist provided by mid-drive motors.

Repairs And Maintenance Cost

Mid-drive motors are usually more expensive to repair and maintain compared to hub motors because they are more complex, put more wear and tear on the drivetrain components, and have more moving parts. Besides, a mid-drive motor can be more complicated to install than a hub motor.

Hub motors, on the other hand, are simpler and easier to maintain, which can result in lower repair and maintenance costs. In fact, electric bikes with hub motors tend to be more reliable and durable than mid-motors, leading to a longer lifespan than mid-drive e-bikes.

Pricing

Due to their simpler design and lower manufacturing costs, hub motor electric bikes are much more affordable than mid-drive e-bikes.

So, if you are on a tight budget, then the hub motor wins the race. You can save 600 to 1000 by choosing a hub-drive electric bike instead of a mid-drive.

Final Thoughts

In conclusion, the choice between a hub motor and a mid-drive motor for an electric bike will depend on individual needs and preferences for example the range you need, the type of terrain you will ride, your budget, etc.

Hub motor e-bikes offer a simpler, more affordable option for riders who prioritize ease of use, while mid-drive motors offer a more advanced, customizable option for riders who prioritize performance and control.

If you prioritize ease of use, affordability, and stability, a hub motor e-bike may be the way to go. But if you’re looking for a more advanced, customizable, and high-performance option, a mid-drive motor e-bike is worth considering.

No matter which type of motor you choose, with the right electric bike, you’ll be able to enjoy a new level of freedom, efficiency, and convenience on your next ride.

Everything You Want to Know About E-Bike Motors, Explained

The 411 on the motors that power pedal-assist and more.

By Dan Roe Published: Apr 14, 2022

You’ve heard of (or maybe even already own) an e-bike, a two-wheeler that helps power your pedaling via a motor. The battery-operated bikes have become more widespread (and less expensive!) over the years. But they still conjure up some questions about how exactly the motor works and what it means for the riding experience. So we researched the growing e-bike industry to find out everything we could about the motors and the way they interact with both the bike and the rider.

In doing so, we talked to three experts: Justin Lemire-Elmore, founder and owner of Grin Technologies, a Vancouver-based engineering company that specializes in DIY e-bike kits; Pontus Malmberg, founder of Blix Bikes and co-designer of SpinTech hub-drive motors; and Jonathan Weinert, Ph.D., director of strategic marketing, global mobility, for Gates Corporation, working on bikes and e-bikes. Here’s everything you need to know about e-bike motors.

compare, mid-drive, motors, electric, bikes, advantages

4 Best E-Bikes You Can Buy Right Now

Electric Bike Company Model X

Order online, arrives fully assembled.

Aventon Pace 350

Cheap and reliable step-through.

Rad Power Bikes RadRunner

Affordable, powerful, and ships immediately.

Aventon Level Commuter

Powerful and perfect for your commute.

In This Guide

In the following explainer, we’ll review these e-bike motors topics:

From Bicycling

We hope you’ll walk away with a better understanding of the technology, if only to satisfy your curiosities about bikes that go whirrrrr.

How E-Bike Motors Work

Fundamentally speaking, electric motors translate electrical energy into mechanical energy. E-bikes use brushless DC motors, or BLDC motors, meaning they don’t use brushes to alternate the direction of current flowing to the motor, as older electric motors did. Those brushes made the motors less efficient and tended to wear out over time, so brushless motors have been the standard for more than a decade.

Brushless electric motors use permanent magnets and electromagnets to turn electrical energy into mechanical energy.

Open up a BLDC motor and you’ll see a bunch of wires wound around a circular series of poles. That’s the stator; it becomes an electromagnet when the motor controller draws current from the battery into the wires. You’ll also see a circular series of permanent magnets, either directly inside or outside the stator. The orientation of the magnets relative to the stator depends on the type of BLDC motor, but either way, that’s the rotor.

Grasping the interaction between the rotor and the stator is crucial to understanding how e-bike motors work. When current runs through the stator’s electromagnets in a circular sequence, those electromagnets repel and attract the permanent magnets on the rotor, causing it to spin. The stator is attached to a shaft. On a mid-drive motor, the shaft spins to generate torque, and that torque gives you pedaling assistance via a small chainring connected to the shaft. On hub motors, the shaft becomes the axle and therefore doesn’t spin. Instead, the rotor itself spins, causing the entire motor (hub) to spin, thus creating torque to spin the front or rear wheel.

How Motors Work With the Rest of the E-Bike

In addition to the motor, all e-bikes have motor controllers and batteries. The controllers modulate the amount of power flowing to the motor, which uses your input to transfer the desired amount of current from the battery into the motor. “What makes an e-bike an e-bike is the experience of how power is being doled out,” Lemire-Elmore says.

Pedal-assisted e-bikes might use a speed (a.k.a. cadence) sensor, which regulates e-assist by detecting the rider’s pedaling cadence, or torque sensors, which sense how much torque the rider is putting into the pedals. Some e-bikes have throttles that allow you to use the motor independent of your pedaling, although regional laws define where you can and cannot use throttle-equipped e-bikes.

Related Story

The Different Types of Motors

Despite sharing the same basic tech, the motors you’ll see on today’s e-bikes come in three basic variants. Mid-drive motors are positioned at the center of the bike’s frame, where you’d normally find the bottom bracket. Hub-driven e-bikes have motors within the front or rear hub, and there are two types of hub motors.

Direct-drive hub motors, apart from their bearings, have no moving parts: The motor just spins around the axle, which is secured to the frame’s dropout. Geared hub motors use a series of planetary gears to lower the motor’s RPM and increase its torque output.

You’ll also find aftermarket e-bike kits that allow you to equip a standard bike with a mid-drive or hub motor, and among aftermarket kits, there are friction drives, which use a spinning wheel that contacts the rear tire to create propulsion.

Mid-Drives

Mid-drive motors are located between an e-bike’s cranks. An electric motor generates torque that spins a shaft that’s connected to a chainring. The motor is therefore supplementing your pedaling power within the bike’s chain-drive, rather than adding an additional power source. There’s also a gear-reduction system within the motor pack. Bosch mid-drive electric bike motors spin hundreds of times per minute—much faster than you could pedal—so the motor’s internal gearing reduces the RPMs at the shaft, therefore optimizing the system’s performance to a rider-friendly cadence of 50 to 80 RPM, Bosch’s Weinert says. All but the lowest-end mid-drive systems include gear sensors that cut the power to the motor while you’re changing gears to avoid breaking the chain while the bike isn’t in gear.

Direct-Drive Hub Motors

A deconstructed direct-drive motor. The hub and rotor (the left item with the magnets) spin around the stator (the center item with the wiring).

Direct-drive hub electric bike motors are the simplest e-bike motors. The motor’s shaft becomes the rear axle. Because the shaft is fixed in place, the motor (a.k.a. the hub) spins around the shaft, propelling you forward. Direct-drive motors tend to be larger in diameter than geared hub motors, Grin Technologies’ Lemire-Elmore says, because bigger hubs mean increased leverage and higher torque outputs, which is needed to supply adequate power at lower RPMs. Direct-drive e-bikes can also generate electrical energy during braking in a process called regenerative braking.

“Motors are perfectly bidirectional,” Lemire-Elmore says. “They can go forward and backward with equal efficiency.” When you squeeze the brakes, a cutoff switch tells the motor controller to become a generator, and the resistance generates electrical energy. The energy regained from regenerative braking is minimal—YouTuber Tom Stanton found an average range increase of 3.5 percent with his regenerative system, although energy gains increase on hilly routes—but the primary benefit is brake-saving stopping power on long descents, as the braking energy is absorbed electronically rather than through friction.

compare, mid-drive, motors, electric, bikes, advantages

Geared Hub Motors

A deconstructed geared hub motor. The planetary gears (second from left) slow down the speed of the hub (right).

Geared hub motors operate like direct-drive hub motors, except that within the hub, there’s an electric motor that spins at a much higher speed. That motor’s shaft connects to a series of planetary gears that connect to the hub, spinning the hub at a lower speed. This method generates more torque, but less top-end speed.

Geared hub motors tend to be smaller in diameter than direct-drive motors because they don’t need as as large of a motor to generate the same amount of torque on the wheel, but the planetary gears also make the hubs wider. The motors also include a freewheel: That means there’s no potential for regenerative braking, but they’ll coast freely instead of creating minor drag when they’re not under power, which makes geared hub motor-equipped e-bikes ride more like traditional bicycles.

Friction Motors

Friction-driven e-bikes seem archaic compared to those with contemporary hub motors and mid-drive systems, but the low-cost design has merits for cyclists who want to convert a traditional bike with minimal effort. A bolt-on motor drives a small wheel that contacts the tire, usually below the chainstays or above the seat stays, although some kits attach to the fork’s brake mount. The motor’s wheel spins the tire, driving you forward. The friction means increased tire wear, but the upside is that the kits are easily interchangeable between bikes. You won’t find friction drives on new e-bikes because they tend to be cumbersome and less efficient, but all-in-one kits like this one from Alizeti are among the easiest ways to electrify a standard bike.

DIY Systems

If you’re technically inclined and don’t mind getting your hands dirty, you can retrofit almost any bike with a hub motor or mid-drive system. Choose the motor, method of pedal assist, and battery size to fit your needs with aftermarket e-bike kits. The Bafang G310 geared hub motor systems are a favorite among e-bike manufacturers, for instance, and the entire DIY kit costs between 479 and 2,393, depending on your selection of components.

4 Folding E-Bikes

Rad Power Rad Power RadMini

Fat tires, and disc brakes for off-road fun.

Aventon Aventon Sinch

Fun, folding fat bike almost always in stock.

Tern GSD S10 Folding Electric Bike

A folding electric cargo bike with passenger footrests? Heck yeah!

e-Joe e-Joe Epik Carbon

Mag wheels and a hidden battery

Mid-Drive Motors vs Hub Motors

Deciding between a hub-driven or a mid-drive e-bike means evaluating your priorities in a bicycle. With that in mind, these are the pros and cons of each design.

Mid-Drive Pros and Cons

Generally speaking, mid-drives climb steep hills more efficiently than hub-driven e-bikes because they can use the bike’s existing geared drivetrain to take advantage of higher gear reduction for low-speed climbing, rather than supplementing it as an additional non-geared power source. (The efficiency disadvantage happens when a hub motor isn’t spinning at its optimal RPM—a powerful geared hub motor should be just as efficient as a mid-drive.) The centered position on the bike also creates a more balanced ride. That, combined with climbing advantage, makes them the go-to motor for e-mountain bikes.

Changing tires on mid-drive e-bikes is easier because there’s no wiring between the frame and the hub, and that allows users to run any wheelset.

The downside of adding a mid-drive motor to a chain-driven bike is increased chain wear. Respectable e-bike manufacturers won’t skimp on chain quality, but the added torque means you might be replacing chains more often. Mid-drives are also more expensive because they contain more mechanical components and higher gear reduction, which drives up cost.

Hub-Drive Pros and Cons

Because hub motors operate outside a bike’s chain drive, they don’t wear down chains and cogs like mid-drives can. They’re also cheaper because they’re mass-produced in much larger quantities and don’t require manufacturers to alter a frame to fit a specific motor.

Hub motors, especially direct-drives, don’t climb as efficiently as mid-drives. “If you’re cruising uphill at low speed and the motor is spinning at low speed as well, you’re turning a lot of that power into heat rather than forward motion,” Weinert says. The higher wattage required by direct-drive hub motors means bigger motors and batteries, which adds weight.

Weight distribution isn’t as centered, either, although the effect on the bike’s handling depends on the weight of the motor. Lastly, changing tires can be tedious because you’ll need to disconnect the wires that power and control the hub motor.

4 Fat Tire E-Bikes

SONDORS X

Rad Power Bikes RadRunner 1

This e-tility bike has front, center, and rear storage.

Aventon Sinch

An innovative in-frame battery allows this bike to fold in two.

Direct-Drive Hub Motors vs Geared Hub Motors

If you’re considering a hub-driven e-bike, find out whether the motor is geared or direct-drive. Each design has its pros and cons.

Generally speaking, geared motors are better for low-speed, high-torque applications, and direct-drive motors are better for high-speed uses. “[Geared motors] can be half the weight of a direct-drive motor that has the same torque,” Lemire-Elmore says, because of the geared motor’s higher internal RPM.

However, because they’re geared down for torque, geared motors struggle to achieve the same top speed as direct-drive systems, which can handle higher speeds and more power without becoming overstressed. Geared motors coast with less resistance than direct-drive motors, although the added coasting resistance of a direct-drive motor is minimal; it’s equivalent to adding another set of tires, says Lemire-Elmore.

Direct-drive motors like this one tend to be tall and narrow. The leverage provided by a bigger stator makes them well-suited for high-speed applications.

Direct-drive motors tend to be bigger and heavier because they require more magnetic material to generate low-speed torque, but that added power and mechanical simplicity helps them operate well at higher speeds. They also tend to be quieter than geared motors, although newer geared motors with helical-cut gears (rather than straight-cut gears) are nearly inaudible as well. Direct-drives can also benefit from modest added range and decreased brake wear due to regenerative braking.

Related Story

What Power Ratings Mean

Attempting to compare e-bike power ratings is a great way to lose your sanity. That’s because “rated power,” the metric some manufacturers use, doesn’t equal a motor’s actual power output or maximum potential power output. “The actual power output of a motor depends entirely on how heavily it is loaded in a given situation and the maximum electrical power that the controller lets flow into the motor,” Lemire-Elmore says. “It has little to nothing to do with a rating anywhere.”

The power rating might indicate how much power you’re getting for a specific amount of time, although there’s no universal standard for peak or rated power duration. “That could be 10 seconds or 30 seconds,” Weinert says. “Some motors quote peak power at 750 watts, but you may only be able to get that for 1 to 2 seconds.”

Here’s how to parse manufacturer jargon. “Power” is a measure of how quickly work is being done. Torque, a metric listed by some manufacturers, is a rotational measurement of force. To determine a motor’s power in watts, you have to know how fast it’s spinning: Torque multiplied by rotational speed equals power. A motor’s power output therefore peaks at a specific amount of revolutions per minute, and even if you knew the RPMs for peak power (good luck getting that figure), you wouldn’t be doing that math midride.

You can get an idea of how much maximum power you’ll actually feel if a manufacturer lists an e-bike battery’s voltage and (continuous) amperage from the motor controller. That’s a better indicator than the motor rating because ratings are arbitrary, but with regards to electrical energy, you can multiply volts by amps to get watts. For instance, the Juiced Bikes CrossCurrent X is rated at 750 watts, a.k.a. 1 horsepower. The battery is rated at 52 volts and the motor controller delivers 20 amps of current. Therefore, 52V x 20A = 1,040W, but you’re not going to feel 1,040 watts because BLDC motors aren’t 100 percent efficient. “It’s probably 75 percent efficient [at that higher power level],” Lemire-Elmore says of the Bafang motor. If the motor is 75 percent efficient, the math says you’ll feel a maximum of 780 watts of peak power, which is pretty close to the 750-watt motor rating.

By comparison, the Blix Bikes Vika Travel folding e-bike has a motor rated at 250 (continuous) watts, yet the battery is rated at 36 volts and the motor controller lists 18 amps. Even if the motor loses 25 percent of input power to inefficiency, the theoretical maximum output power should be 486 watts, which is almost double the 250-watt rating. Crucially, Blix notes the bike’s 250 watts are continuous, while Juiced Bikes doesn’t say how long its 750-watt figure can be sustained.

Torque is less subjective. If a manufacturer lists an e-bike’s peak or sustained torque in newton metres, go with that. Better yet, percentages of support (as Bosch lists) tell you how much help the motor is giving you at a given level of e-assist. Otherwise, if you’re dying to know how much power your bike can produce for a sustained period of time, we’d recommend reaching out to the manufacturer and asking for the meaning of the bike’s power rating before you buy.

The best electric bike conversion kits 2023 and how to fit them

The best electric bike conversion kits can give you an extra boost of power without the expense of purchasing a new electric bike. We’ve fitted some of the best e-bike conversion kits ourselves, so will walk you through the process, how easy it is and how the different systems perform.

E-bikes are soaring in popularity – and for good reason. The best electric bikes replace a car for running errands around town and greatly increase the distances it’s possible to ride on one of the best commuter bikes. An e-bike can also be a great tool for boosting your fitness, whether that’s enabling you to ride with a greater range of people or offering the motivation of a greater range of roads to explore.

But is an e-bike worth it,? As the best ebike conversion kits promise to add power to an ‘analogue’ bike for a lot less than a full ebike, it’s an easy, cheaper way to get an electric boost.

In this guide we’ll take you through the surprisingly broad range of benefits an e-bike conversion kit has to offer and – most importantly – how to perform an e-bike conversion, based on our hands-on experience. For a walk-through on how to do it, you can check out the video above or read on for a step-by-step guide – it genuinely is so much simpler than you would think.

When buying an ebike conversion kit there are a number of factors you’ll need to consider. Most importantly you’ll need a kit that will fit your bike. To help with this it pays to take a few frame measurements, notably the width of your forks and the width of the rear stays, as well as noting the wheel size and the type of brakes. You can then match these details to the kit specifications.

Naturally you’ll also need to consider the cost and how much you chose to spend on an ebike conversion kit will be dictated by not only your budget but also your needs. If you’re unsure of just how much you’ll use the converted bike then it’s prudent to opt for a cheaper kit. you can always upgrade down the road.

You’ll also want to consider where the motor will be located, and match this to your bike and your mechanical prowess. Front hub motors are typically the easiest to fit, while mid-drive motors require more effort. A rear hub motor lies somewhere in between the two, and like a front hub option is applicable to a wide range of bikes.

Other considerations include the type of battery and the wattage rating. 36 or 48 volt battery is standard, with wattage usually running from 300 to 600 watts.

The Swytch kit is super-simple: just swap out your front wheel, wire up the controller and battery and you’re off. The battery is also very compact, allowing you to remove it from the bike easily to carry with you.

The TongSheng kit positions the motor at the centre of the bike, so it will fit to a wide range of designs. It’s lightweight for its high torque and power output, although you’ll need to buy the battery separately.

The Voilamart kit is an inexpensive rear wheel conversion option, although you’ll have to source a battery separately. It’s slightly fiddly to fit as well and requires additional waterproofing if you plan to ride in wet weather.

The best electric bike conversion kits

You can trust Cycling Weekly.

Our team of experts put in hard miles testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.

Specifications

Wheel sizes: Each wheel is custom built – specify your required size at checkout (Bromptons also catered for)

Reasons to avoid

The newly updated Swytch system is one of the simplest conversion kits to fit out there. The latest version, launched in August 2022, has a smaller, neater battery pack that improves the bike’s dynamics and lowers its weight. There’s the choice of the Air battery (700g, range 15km) or the Max battery (1,100g, range 30km). Both use the same mount, which places the battery to the front of the handlebar.

The motor sits in the front hub and we found it to be pretty discreet. Incidentally, the new batteries will work with the original motor and pedal sensor, so if you already own the original kit you can upgrade it with just a new battery without having to buy the whole kit again.

The Swytch kit is incredibly easy to fit. It took us around 30 minutes working at a steady pace.

We tested it on both a reasonably light two-speed steel bike and a heavier Pinnacle utility bike. It transformed the ride of the two-speed bike, making it fast, nimble and responsive. We also found the stated range to be conservative: after 20 miles on setting number two (medium assist) it had only used two bars out of five on the battery.

With the heavier Pinnacle on maximum assist (and on draggy routes) we were getting slightly under the 30km for the Max battery. As with all e-bike batteries, range depends on the terrain, weight of bike and level of assist.

Great customer support makes this one of the best kits for people who are new to working on their bike and who aren’t familiar with electrics. And even if you do have a strong background in both those areas, a simple system is always appreciated.

Reasons to avoid

Like the Bafang mid-drive system below, the TongSheng offers the same benefits of compatibility with a wide range of bike designs and a high torque for steep hills and off-road terrain. However, the TongSheng mid-drive does manage to be a little lighter than the Bafang for approximately the same power.

This model doesn’t come with a battery included, so you’ll have to source your own 36v item. As a rule of thumb, around 10Ah will give a range of 29km / 18mi, whereas going up to 18Ah will typically give around 53km / 33mi, so be sure to factor that in when you’re making your choice.

There’s a huge range of batteries sold on Amazon, but Green Cell is a particular brand we’d recommend.

We found fitting to be reasonably easy. As with most mid-drive systems, you replace your crank and chainring with the one provided in the kit. There’s an LCD display for attaching to your handlebars and you’ll need a battery to be hooked up to the motor.

Read more: TongSheng TSDZ2 conversion kit review

Reasons to avoid

A mid-motor drive system offers a number of benefits over hub-driven conversion kits. With the power delivered at the cranks it can produce more torque, making it more effective on particularly steep and bumpy terrain.

Another perk is that the compatibility is much greater – no concern about wheel diameters, hub widths, axle standards and brake type. No matter whether you’re running rim brakes or disc, quick release or thru-axle, the crank driven system is compatible with all.

The only proviso is that the frame material must be alloy and the bottom bracket width is 68–73mm – but that covers most bikes you’re likely to be fitting this system to.

There are a few aspects to be aware of, the first being that this system doesn’t include a battery and that typically makes up about half the cost of a conversion kit. Finding an e-bike battery is quite straightforward with many being sold on Amazon, with Green Cell being among those we’d recommend.

Just make sure to get a 36V one for this motor as a higher voltage can damage it. Also you should be aware that capacity of 10Ah will give you a range of about 29km / 18mi, while a capacity of 18Ah typically gives about 53km / 33mi – so be sure to factor in the distances you’re planning on riding.

Reasons to avoid

This radically different approach from Rubbee makes for an e-bike conversion with much fewer parts. The battery and motor are housed in a single unit which powers the bike directly turning the rear wheel with its integrated roller.

Not only is the initial installation notably fast and easy, the quick release system means that you can take off the unit for rides that you don’t wish to be assisted on. At 2.8kg, it doesn’t add much weight to that of the bike, making the bike easier to handle.

The range of this model is quite low, limited to Eco mode it only offers a range of 16km / 10mi – although taking the device off to charge at the other end is easy to do and it only takes an hour to top up. There is the option to increase your range by buying additional battery modules that fit into the base unit.

Up to three can be accommodated, which in turn increases the maximum range to 48km / 30mi, or around 23km / 14mi with moderately heavy use. However, unlike many other e-bike systems, the Rubbee X supports regenerative braking, allowing you to scrub back some power on the descents.

Reasons to avoid

Bafang is a well established maker of electric bike motors and offers a front hub based motor, if you’re not a fan of the bulky profile a mid motor conversion system creates. You can buy this kit without a battery – although why would you? – but if you sensibly also opt for a power-pack there’s a choice of amp hours, and you can select either a downtube or a rear-rack mounted version.

The setup follows the same principles as most front-wheel e-bike conversions. First you need to set up the wheel with a disc rotor, tyre and inner tube and install that into the bike. Then attach the cadence sensor – so it can tell when you’re pedalling and need assistance – then attach the battery and the LCD display and you’re essentially good to go!

It’s worth bearing in mind that although this conversion kit comes in many different wheel sizes, it is only compatible with bikes that have a front disc brake and a Quick-Release axle. If your disc brake bike is a newer, more expensive model, it might not be compatible, so worth checking first.

Remember, that in the UK electric bike laws mean that e-bikes are not permitted to have a power output of more than 250w and shouldn’t propel the bike when it’s travelling more than 15.5mph – you’ll have to make sure you select the right model with the relevant limitations.

Reasons to avoid

We’ve also tested the Voilamart kit, which comes with six main parts: the replacement rear wheel, the replacement brake levers, the control screen, pedal sensor, throttle and the control box. It doesn’t come with a battery however.

On review we found the kit pretty straightforward to fit, although you’ll need to remove the bike’s crank to fit the pedal sensor and this element of the conversion was a bit fiddly. Another potential drawback is that the connectors, which link to control unit, aren’t waterproof, with only a bag supplied to house the delicate electronics. While it does a good job of keeping everything tidy, we decided to buy a plastic enclosure, cut the wires to length, solder the connections and then heat shrink for added protection.

As for the ride, the rear wheel kit delivers plenty of power. However, since the pedal sensor only detects when you’re pedalling rather than how hard you’re pedalling it delivers the power as soon as your start to turn the crank arms. Fortunately, you can quickly adjust the level assistance, with five power options available.

All in all the Voliamart rear wheel kit is an affordable way to ‘go electric’, although it requires you to be mechanical competent to fit it and you’ll need to factor in the additional cost of a battery.

How to convert your bike to an e-bike in four steps

Here’s our step-by-step guide to how to add an electric bike conversion kit to your pedal-powered bike.

Swap the tyre and tube

Firstly, remove the tyre and tube from your current front wheel and then install them on the new wheel from the kit. Make sure to check if the tyre is directional, if it is, ensure that the tyre is mounted so that the cable sticking out of the hub is on the left-hand side (non-driveside) when the wheel is installed in the bike – otherwise it’ll be powered in the opposite direction to your direction of travel!

To swap the tyre and tube over, you will need some tyre levers and a pump. If you want to go over how to do these, we have a guide that can be accessed here.

Final points are to do up the nuts on the wheel’s axle to keep it firmly in place in the forks and to check that the brakes are correctly adjusted for the new wheel. If you’re unsure how to do that, we have another guide here.

Attach the bracket to the handlebars

There is a strap that needs to be attached to the bars to keep the bracket in place and stop it rotating around. There are also some adaptors included in the kit which can be used if your handlebars are a little skinnier.

But essentially all that’s needed to be done here is a couple of screws to clamp the bracket tightly to the bars.

Attach magnet disc and sensor

The magnet disc has a split design so it can just clip around the inside of the left (non-driveside crank) and is then held in place by its retention ring. Next, stick the sensor on the frame directly in line with the magnets – this will ensure that the sensor can tell when the cranks are moving.

Plug in the cables

The thickest one is the main power cable and that just needs to be plugged into the cable extending from the hub. The other orange cable attaches to the cadence sensor and this just needs plugging in as well.

It’s then a good idea to use some cable ties to tidy up the lengths of the cables a little bit, so they aren’t flapping about and risk getting caught on the spokes or on the cranks.

The blue cables, you don’t need to worry about, these are for an optional brake sensor upgrade kit.

Why convert your bike to an e-bike?

What types of conversion kit are available?

You can get conversion kits that power your front or rear wheel or power the bikes via the cranks.

Wheel-based systems usually have a hub motor and require replacement of your existing wheel with a compatible motorised one.

The alternative is a system like the Rubbee that drives your wheel by pushing on the tyre. Tyre wear can be an issue here though.

Finally, there are systems that power the e-bike via the bottom bracket.

Usually the e-bike’s battery will bolt onto your frame or be attached to your handlebars, although sometimes you can fit a battery pack to a rear rack.

We’ve more on compatibility. which can be an issue. below.

How much does it cost to convert a bike to an e-bike?

vary depending on the type of conversion kit and the size of the battery. To give a rough Band, you can expect to pay a total of between £500 and £800 from a reputable brand, but there will be outliers at either end.

Is it worth converting a bike to an e-bike?

There are many reasons to upgrade your bike to offer a little e-assistance. On the one hand, it can greatly increase the usefulness of your bike, enabling you to replace short car journeys – such as around town, to the shops, or to work – with going by bike instead.

It’s a lot more environmentally friendly getting about on two wheels than in a two-ton metal box. It can also save you time – bikes are able to take more direct routes and are less affected by traffic, as well as eliminating the need to search for a parking space at the other end.

But beyond just their practical benefits, e-bikes can also be a potent tool for boosting your fitness. Consistency is key when it comes to exercise, so making commitments with friends is a great way to ensure you’re heading out the door. Previously, differing fitness levels could make it difficult to find a riding partner but with an e-bike levelling the playing field, getting in a productive workout (for both of you) with a friend is much easier to do.

Added to that, an e-bike can be much more motivating in that it opens up a far greater range of roads than you’d be able to access just under the power of your own two legs. Exploring new roads is part of the fun of riding a bike and an e-bike can help preserve that.

Can you convert any regular bike to an e-bike?

Most bikes can be converted to an e-bike – it just requires getting the matching the right conversion kit to match the specification.

For conversion kits where the motor is located at the wheel’s hub, you’ll need to consider the wheel’s diameter, the width and axle standard of the hub and whether it uses rim or disc brakes. For instance, a 700c (AKA, 28”) disc brake wheel with a 100mm wide quick-release hub is a relatively common spec. Once you’ve determined what type of wheel you need, the conversion is quite a straightforward process

Crank driven systems are generally easier in terms of determining compatibility; the requirements are typically just an alloy frame and a bottom bracket width of between 68 and 73mm – which is the standard for all road and mountain bikes, it’s only specialist bikes that have a different spacing there. In replacing the crankset, these systems are a bit more involved to fit than a hub system, but still well within the remit of a home mechanic.

Other kits, such as those that directly drive the rear tyre, have almost universal compatibility – provided your tyres aren’t too heavily treaded.

Are electric bike conversion kits any good?

You won’t be getting the very best motors and the largest, seamlessly integrated batteries with an e-bike conversion kit. But with that said, e-bike conversion kits are much cheaper than purchasing a whole new e-bike and they do deliver many of the same benefits.

Converted e-bikes are great for commuting and utility cycling, giving that extra boost to help flatten hills, motor along the flat and lug about heavy loads. E-bike conversions are also good for leisure cycling, helping to moderate your effort level as needed and greatly extending the range you can explore.

For more specialist utility needs, buying a new cargo e-bike would help boost your carrying capacity and range. Equally, for the aesthetically conscious, the latest breed of e-road bikes are almost indistinguishable from a non-powered bike at first glance. Then again, both those options are much more expensive than a conversion.

How we test

Where we’ve been able to link to a review, it means that we’ve put the ebike conversion kit through its paces. We’ve assessed how easy it is to fit and maintain as well other factors such as quality of the components and battery life and charge time. Riding the bike once fitted with the kit, we’ve taken into account the ride quality, the ease of use and the battery range.

Where we haven’t yet had the chance to review an item, we’re still confident in recommending it as one of the best, because we either know the brand really well, and have probably tested another product or the previous version and can still happily recommend it as one of the best.

What is a Mid-drive Ebike Motor and How Good Are They?

Electric bikes have 2 different options when it comes to the drive system. The motor is either in the hub of the wheel, helping provide power through the wheel (usually the rear), or it is in the lower, middle section helping you pedal the cranks.

A “mid-drive” motor system is where the motor is near the middle of the bike, down between the crank arms to which your pedals are attached.

Quickly Ride to a Section.

The advantages of a mid-drive ebike system are –

  • Best ebike motor brands
  • Best efficiency
  • Smoother ride
  • Better weight distribution
  • Easier to service
  • Better looking (In my opinion)

Some disadvantages are –

In this article, I will go in-depth into both the advantages and disadvantages of mid-drive ebike systems, how they work, and why you may want to choose one.

The advantages of a mid-drive electric bike

The Best Ebike Motor Brands (are all mid-drive only!) –

(These are the motors found in the majority of mid-drive ebikes in the US)

#1 Bosch

Bosch stands out as a leader in the ebike industry. Bosch takes the same ingenuity that they put into their home appliances, power tools, and industrial machinery, then applies it to their electric bike motors.

Bosch also produces their own batteries and controllers so that they all work perfectly together. They offer a motor and battery combination to suit any riding style.

There are many Bosch certified technicians across the US, (I happen to be one of them), and Bosch continually updates their firmware which can then be transferred to your bike at your local Bosch certified shop.

  • Purion – Basic handlebar display for speed, trip miles, odometer, range, battery
  • Intuvia – Bigger display on the stem and has more metrics than Purion
  • Kiox – Color stem display with even more metrics and Bluetooth capable
  • Smartphone Hub – Has a basic readout, but paired with a phone, skies the limit
  • Nyon – Larger color stem display with built-in GPS mapping, Bluetooth, and Wi-Fi
  • The new Smart System Led Remote and Kiox 300 (2022) – coming soon

You can upgrade your Bosch display at any time, they are backward compatible.

If you are looking for the best ebike system available, get a Bosch!

#2 Shimano

Shimano has been the leader in the bicycle parts industry for decades. Shimano electric motors are some of the most compact and reliable on the market. As ebikes have gained popularity, Shimano continues to expand the electric bike motors they offer.

Shimano also uses its own battery systems and displays for fully compatible integration. Shimano displays are simple, sleek, and give you the information you need.

Shimano makes one of the best ebike motors available, with amazing range and they are a great choice for an electric bike.

#3 Yamaha

Yamaha is known for its motorcycles but has been making electric bike motors for quite some time now. They now have many different options to fit your needs.

Yamaha started with 2 motor options and now has 5 available. If there is any indication that ebikes are here to stay, it’s how quickly these companies keep adding and improving motors to their line-ups.

  • Display A – basic handlebar display for speed, trip miles, odometer, range, battery
  • Display C – large display on the stem with more metrics and Bluetooth
  • Interface X – smaller, sleeker stem display with Bluetooth and ANT

I have had many customers over the years thrilled with their Yamaha systems. Their range is top-notch.

#4 Brose

Pronounced /bro-sah/, Brose started out making motors for power steering in cars and has since gone all-in on the electric bike market. Brose motors are some of the smallest and quietest available today.

Brose used to just make motors and allow bike manufacturers to use whatever battery fit their designs, but they have now begun to use their own battery systems for full integration.

  • Allround – Basic handlebar display with essential metrics
  • Remote – minimalist handlebar display with assist level lights
  • Central – bigger, easy to read stem display

Brose makes a solid, quiet motor and now that they are using their own batteries, they are a great choice.

Mid-drive Motors are The Most Efficient for Ebikes

The majority of mid-drive motor electric bikes are sold in Europe. (The US is catching up)

With Europe regulating motors to 250 watts without a license, these brands now only offer 250w motors.

What is great about this is that these companies have used their combined resources to get the most power out of a 250w motor. With mid-drive motors the power is not directly linked to how many watts the motor can run at, but rather how many newton meters of power the motor can supply.

I have included a chart at the bottom of this post that details all of the different systems these brands offer and how powerful they are.

Mid-drive Motors Offer the Smoothest Ride

All 4 of these brands are pedal-assist only. None of them have a throttle option. Throttles can be useful for some but can make the ride a lot more inconsistent. With pedal assist, you are pedaling the bike like a regular bike, just with less effort, this makes it feel more like riding a bike than being on a moped.

Mid-drive motors are directly connected to the front chainring on your bike allowing power to be transferred with little disruption. You simply start pedaling and the motor will help out at the assistance level you set.

Mid-drive Motors Distribute Weight Evenly

With a mid-drive motor, the motor sits centered on the bike at the lowest point on the frame. This keeps the balance of the bike even and can actually make your ebike feel more stable.

Most did-drive set-ups also have the battery on the down tube of the frame just in front of the motor, keeping battery weight and placement from having much effect on your balance.

Keeping these heavy components centered and low on the bike is key to keeping the bike well balanced.

Mid-drive Motors are Easy to Service

For me as a bike mechanic, this is a big one.

One of the best reasons for you to consider a mid-drive electric bike is that all the actual bike components (wheels, shifters, brakes, derailleurs, gearing, etc.) are standard bike components that you can find at any local bike shop. (or they can order them)

This means that if you are traveling and have an issue with your ebike, you can take it to any local bike shop (it doesn’t have to be the shop you bought your bike at) and they should be able to help you out, even if they don’t carry electric bikes.

Also, all of these companies have great warranties that will cover the electric components for up to 2 years. If you do have a problem with your motor or battery, it will usually happen in the first few months.

Mid-drive Motors Look Good

I believe if you can have function and form then that’s a win-win. Mid-drive motors are integrated into the design of the frame and have gotten smaller and more powerful in the last couple of years.

These top brands work directly with the manufacturers of the bikes to make sure the motor and battery are seamlessly integrated into the design of the bike. Some ebikes now don’t even look like they’re electric bikes. With batteries being concealed in the frame and the motors hidden behind the cranks, mid-drive ebikes simply look amazing.

The disadvantages of mid-drive electric bikes

Mid-drive Motors are Expensive

With all the advantages listed above and all the technology being used to make these motors awesome, there is a cost. A mid-drive electric bike can cost 2 to 3 times as much as its hub-drive counterpart.

Bicycle manufacturers have had to completely redesign their electric bikes in order to integrate the motor and battery. The good thing about this is that the bikes are built specifically with electric motors and extra power in mind. They didn’t just strap motors to their existing bikes and send them out the door.

Keep in mind –

  • Though mid-drive electric bikes cost more upfront, they will last longer and cost less to service.
  • Long term, the cost of a mid-drive ebike is often negated by the quality they provide.

The Best Mid-drive Electric Motors do not Have Throttles

None of the brands listed here have a throttle option. There are some mid-drive motors that offer a throttle but they do not make my top 4 list.

Bafang makes a mid-drive with a throttle. Currie used to, but I don’t think they do anymore. Pretty much any modern mid-drive electric bike is going to be pedal assist only. The vast majority of electric bikes with throttles use a hub-drive system.

If you would like a mid-drive electric bike with one of the best motors but think you may also need a throttle, I would recommend trying a mid-drive ebike at your local shop first. I have had many people come into my shop, convinced they want a throttle, but once they try a mid-drive ebike they realize how easy they are to ride without a throttle.

Leave a Comment