Our rigorous lab tests reveal the UK’s best e-bike motor systems, found on top electric bike brands such as Giant, Halfords and Trek. Find the ones that can truly support you, letting you go further with less effort
Electric bikes (also known as e-bikes) are a fantastic way to rediscover a love for cycling, let you go further and extend your enjoyment into your later years.
They don’t come cheap, though, and we’ve found that some will take you much further than others. Make the wrong choice and you could end up with an electric bike that will take you only 30 miles on flat ground, and won’t get you up even the shallowest of hills.
However, the best we’ve tested will have you climbing hills with ease and power you along a flat road for nearly twice as many miles. Read on to find our why we test electric bike motors, the best motor/display combinations and some of the top brand models that have them.
The secret to choosing the best electric bike
The most important part of an e-bike is its motor and display combination. If this performs poorly, there isn’t much point in spending the extra money that an e-bike costs over a traditional bike. While there are many brands, there are only a few manufacturers (such as Bosch, Shimano and Yamaha) that produce e-bike motors.
Consequently, many models use the same motor and display combinations.
Therefore, our independent lab tests focus on electric bike motors and displays. Armed with this information, you can narrow your search to just those that have the motor/display combo that you want.
Most retailer sites let you filter your search by the type of motor, but we’ve also listed a selection of e-bikes with each motor review, chosen from the most popular brands among owners. Be aware that some retailers will sell the same e-bike, but with a different motor.
If you find one we’ve listed at a different retailer, we recommend you double check the specifications to ensure it has the motor you’re after.
Best electric bike motors for 2021
Below is a summary table of all the motors we’ve tested, so you can compare their scores and pick the one that’s right for you.
Bosch Active Line with Purion display (400Wh battery)
Range: 32 miles
Bikes with this motor include: Raleigh Felix Step-through Electric Hybrid (£1,900 at Halfords), Trek Verve +2 (£2,600 at Balfe’s Bikes), Trek District+ 1 (from £2,275 at Evans Cycles)
Our verdict: The range of this motor and battery combination isn’t as extensive as some, but could be extended to 54 miles with a 500Wh battery. The range is much shorter on steep hills, less than 10 miles on full assistance on a steep gradient. It’s a decent motor with no major flaws.
The consistency and smoothness of the power delivery is a particular strength of this motor, and it’s also quiet. The Purion display, which has four assistance levels, is visible in bright conditions, plus it’s clear and easy to use. Bosch claims this is a motor for urban travelling, and our test results agree.
A bike with this motor will be great for someone wanting to get around town, but if you’re wanting to go for longer rides or off-road, take a look at a motor with a bit better more hill support.
Bosch Active Line Plus with Intuvia display (400Wh battery)
Range: 43 miles
Bikes with this motor include: Raleigh Felix+ Nexus Hub Step-through Electric Hybrid (£2,250 at Halfords), Trek District+ 6 (£3,050 at Trek Bikes), Kalkoff Image 5.B Move 2021 (£2,464.99 at Rutland Cycling)
Our verdict: The Bosch Active Line Plus motor will take you almost 43 miles on the flat and a little over 13 miles on a steep hill, when paired with a 400Wh battery.
It’s a good, quiet, motor and very smooth with its power delivery. It also accelerates you quickly and without jerkiness up to top speed.
The Intuvia display is the best we’ve tested. It has four assistance levels, provides clear information and is very easy to use.
A bike equipped with this motor and display is a good choice if you want an e-bike that you’ll use mostly for urban travelling, but will still hold up fairly well if you decide to go on a longer adventurous trip.
Bosch Performance Line with Intuvia display (500Wh battery)
Range: 40 miles
Bikes with this motor include: Trek District+ 9 (£4,000 at Trek Bikes), Cube Touring Hybrid Pro 625 2022 (£2,998.99 at Rutland Cycling)
Our verdict: The Bosch Performance Line Cruise electric bike motor with an Intuvia display, is the best electric bike motor and display combination we’ve tested at our lab. The motor is quiet and provides fast acceleration. It also delivers power smoothly and gives brilliant support on flat terrain, and also on tough hills. The Intuvia display is clear, even in bright conditions and is very easy to use.
If you opt for a bike with a large 500Wh battery, you’ll get almost 40 miles of electrical assistance on the flat if you use the highest assistance setting. You can extend the range further if you lower the level of assistance. On steep hills, you’ll still be able to ride for a little under 16 miles with full assistance.
A bike with a smaller battery (400Wh and 300Wh batteries are common) will mean that you can’t ride as far with assistance, 33 miles and 25 miles, respectively, on the flat.
If you can find a bike you like to ride that has this motor and display combo, we recommend you go for it. This motor is best we’ve tested.
Bosch Performance Line with Purion display (500Wh battery)
Range: 40 miles
Bikes with this motor include: Kalkhoff Endeavour 1.B Move (£1,889.99 at Rutland Cycling), Haibike HardNine 4 2021 OUT OF STOCK (£1,999.99 at Rutland Cycling)
Our verdict: The Bosch Performance Line Cruise is the best all-round motor that we’ve tested. It’s a good pairing with the Purion display which gives four levels of assistance and is easy to use.
When paired with a 500Wh battery, you’ll get 40 miles of riding on the flat on the maximum power setting. That drops to 16 miles on a steep gradient.
You can buy this motor with 300Wh and 400Wh batteries, too, which will reduce the range of the bike, but you’ll still get the same smooth ride.
The motor accelerates exceptionally well, is one of the quietest we’ve tested and is brilliant at supporting on flat roads or hilly terrain.
Bosch Performance Line CX with Intuvia display (400Wh battery)
Range: 39 miles
Bikes with this motor include: Trek Powerfly 5 2022 (purion display) (£3,950 at Trek Bikes)
Our verdict: The Bosch Performance Line CX is a good motor, providing fast acceleration, but is noisier than many of the other motors we’ve tested. The Intuvia display gets the full five stars as it’s clear to read even in bright conditions and easy to use. It also has useful extra features, such as USB phone charging and shift recommendation (telling you which gear to be in to preserve the battery).
A bike equipped with this motor will feel smooth to ride. It also offers decent support on the flat and excels at providing support on hills, which is what the CX line is tailored for. Equipped with a 400Wh battery, on the highest assistance level you’ll get about 38 miles of support if purely on flat terrain.
This drops to about 12 miles on steep hills. Of course, most journeys won’t be exclusively flat or uphill, so you can realistically expect a range between these two figures.
For a bike with a 300Wh or 500Wh battery, expect a range of about 29 and 48 miles, respectively, on the flat. If noise isn’t an issue for you, a bike with this motor and display choice has a decent motor efficiency and will get you up those steep hills.
Bosch Performance Line CX with Purion display (600Wh battery)
Range: 60 miles
Bikes with this motor include: Scott Aspect eRIDE 920 (£2,999 at Pure Electric), Cube Kathmandu Hybrid One 500 2022 (£2,699.99 at Rutland Cycling), Trek Allant +5 (£3,100 at Evans Cycles)
Our verdict: The Bosch Performance Line CX with a Purion display is a good motor and display combination. The motor provides fast acceleration, but is noiser than many of the other motors we’ve tested. The Purion display if clear and easy to read, offering four levels of assistance.
A bike equipped with this motor will feel smooth to ride, and offers decent support on the flat, but excels at providing support on hills – being a motor for electric mountain bikes, this is what the CX line is tailored for. Equipped with a 600Wh battery, on the highest assistance level, you’ll get about 60 miles of support if cycling purely on flat terrain.
This drops to about 19 miles on steep hills. For a bike with smaller 300Wh and 400Wh batteries, expect a range of about 29 and 38 miles, respectively, on the flat. If noise isn’t an issue for you, a bike with this motor and display choice has a decent motor efficiency and will get you up those steep hills.
Elops KM790 with Decathlon Elops KM790 display (300Wh battery)
Range: 25 miles
Bikes with this motor include: Electric City Bike Elops 120E (£749.99 at Decathlon)
Our verdict: The Elops KM790 rear motor may be OK for some peoples needs, but there are much better motors out there. With a 300Wh battery, at maximum assistance you can expect to get about 25 miles of range on the flat, or about nine miles climbing up hills.
This motor has one of the lowest miles per watt hour we’ve tested, meaning when its connected to the same-sized battery, this motor won’t get you as far. It’s noisy, with poor acceleration. You’ll get a bit of help setting off on the flat, but it will struggle to give any boost if you start on a steep hill.
Motors with great acceleration will get you up to speed quickly, even when you start on a hill. However, once you’ve got going the support is good, with great support on flat terrain, and good assistance on hills if you’re already travelling at speed. The display isn’t great, with only LEDs to show which assistance level you’re on and the remaining battery.
There’s no information on speed, which even basic displays from other brands show. If you’re only going to travel short distances on roads without many hills, you may get away with this motor.
But if you have a hilly commute, or think you’ll do any sort of off-road cycling, go for a different motor.
Fazua Evation with Smartphone app Display (300Wh battery)
Range: 35 miles Bikes with this motor include: Boardman HYB 8.9E Mens (£2199 at Halfords), Boardman HYB 8.9E Womens (£2199 at Halfords)
Our Verdict: Overall, the Fazua Evation is decent with acceleration being where it shines. The whole Fazua Evation system weighs 4.6kg, adding a bit of weight to the bike it’s equipped to, but not as much as some other systems.
The motor can deliver up to 60 Nm (Neuton metres) of torque (pulling power), which is quite high for an e-bike motor – the higher the torque, the easier and quicker the motor can get the bike going. The acceleration on this bike is excellent and will get you going even when starting on a hill.
Once up to speed, it offers good support up hills and average support on flat terrain. With a 300Wh battery you can expect to get 35 miles on flat terrain and 10 miles up hills – acceptable, but nothing special.
The Fazua system doesn’t have a built in display, but you can attach your smartphone to a bike and use the Fazua app to link the two. The app connects to your bike via Bluetooth, and has a speedometer and GPS navigation, as well as giving you direct access to Fazua services.
We’ve tested better motors, but if you want your e-bike to take to strain out of getting up to speed and are less bothered about it doing all the work once you’ve got going, then this motor could well suit you.
Giant SyncDrive Core with RideControl Charge display (500Wh battery)
Range: 50 miles
Bikes with this motor include: Giant Entour E+1 2021 (£2,039.99 at Rutland Cycling), Giant Entour E+ 3 Low Step Through (£2,199 at Pure Electric)
Our verdict: The SyncDrive Core and RideControl Charge motor/display is a good all-rounder combination. The build quality of the motor is excellent, and provides smooth power delivery.
With everything else the motor is average. It provides decent support on flat and hilly terrain, and the acceleration also middle of the road.
This isn’t a bad thing – it may not be the best motor out there, but it’s by no means the worst. The screen is also decent, being fairly easy to use and operate. With a 500Wh battery you can expect to get a range of about 50 miles on flat roads and 17 miles up steep hills at maximum assistance.
With a 400Wh battery, this will drop to about 40 and 13 miles, respectively. If you want an electric bike that can handle a little bit of everything then a bike with the SyncDrive Core motor review is worth a look.
There are more powerful motors out there, so if you have a particularly hilly commute, or are enjoy mountain terrain, then look for a motor that scores a bit higher for acceleration and hill support.
Giant SyncDrive Pro with RideControl Ergo display (300Wh battery)
Range: 22 miles
Bikes with this motor include: Giant Fastroad E+ 2 Pro (£3,199 at Giant), Giant Stance E+ 1 Pro 2021 (£3,799 at Pure Electric)
Our verdict: This SyncDrive Pro and Ergo display package is average overall, and is mostly let down by its poor range. The acceleration provided by this e-bike motor is nothing special, but it’s enough to get your bike going. The power delivery is excellent, with the motor increasing your speed smoothly. Once at speed, the support is great on flat terrain, but only average when going up hills.
Unfortunately, the motor is power hungry. In our tests with a 300Wh battery, the motor managed only 22 miles of range on the flat and 11 miles uphill. We’ve tested other motors with a similar battery that managed 65 miles, so the SyncDrive Pro’s performance is disappointing.
The display isn’t great, either. The RideControl Ergo has buttons to change the assistance level, but with no display you get very little information or feedback when cycling. It’s compatible with some of Giant’s ANT+ and RideDash displays, but these are a separate purchase.
Alternatively, you can link it to your phone via the RideControl app. If you’re set on a Giant bike, we’d suggest considering the SyncDrive Core over the Pro motor – it gets much more range out of an equivalent battery and apart from slightly less support on flat terrain, performed just as well as the Pro in our tests.
Mahle Ebikemotion X35+ with iWoc One display (300Wh battery)
Range: 47 miles Bikes with this motor include: Cannondale Topstone Neo SL 2021 OUT OF STOCK (£2,899.99 at Rutland Cycling), Orbea Optima E50 (£1,649 at Pure Electric), Orbea Vibe H30 2021 (£2,159 at Pure Electric)
Our verdict: This X35+ motor provides a great range, delivers power extremely smoothly and is almost silent when running. However, it doesn’t provide anywhere near as much support compared with most other motors we’ve tested. With a 300Wh battery, the motor has a 47 mile range on flat roads and 13 miles when travelling uphill. This is a great range and should last you several commutes.
The acceleration is good as well, with the 40 Nm (Neuton metres) torque Pulling power) smoothly accelerating your bike from a standstill. Once up to speed, however, the motor does very little to support you once at 15.5mph on the flat, and not much more when cycling uphill.
If motor noise is an important factor for you, you’ll be pleased to hear that this motor is virtually silent while running.
The iWoc One display doesn’t have a built-in screen. Instead, it houses a single button that lets you move between settings, while a multicolour LED ring displays battery and the current assistance level.
Although the iWoc One display lacks the functionality of other models, the single button makes changing settings much easier to do while cycling. If range is your key priority, a bike with this motor may appeal. For everyone else, we recommend looking for an e-bike with a motor that gives better support overall.
Shimano Steps E5000 with SC-E6100 display (500Wh battery)
Range: 48 miles Bikes with this motor include: Gazelle Citygo C7 HMS 2021 (display not given) (£1,614.99 at Rutland Cycling), Ridgeback X2 (SC-E5000 display) OUT OF STOCK (£2,699.99 at Ridgeback)
Our verdict: Shimano claims that the Steps E-5000 motor is very quiet, and our rigorous tests prove this to be true as it’s virtually silent while running.
The motor also offers impressive assistance. It received a software update in 2021, resulting in it now getting four stars out of five for the support it provides when cycling up steep hills.
This is a big improvement to its previous two-star rating. It’s acceleration is OK, but there are some motors out there with a more powerful start. The SC-E6100 display is adequate, offering four levels of assistance and a clear display. It also comes with wireless Bluetooth communication, so you can use a third-party display or smartphone app.
The sheer amount of information shown on the display can make it feel cluttered at times. With a 500Wh battery, you can get about 48 miles on flat terrain and 14 miles up hills while on the maximum assistance level.
You can increase those ranges by lowering the assistance level. A bike with this motor/display combo would be a great choice for city commutes, but for more challenging terrain we recommend a motor with a better acceleration.
Shimano Steps E6100 with SC-E6100 display (500Wh battery)
Range: 64 miles Bikes with this motor include: Kalkhoff Image 5.S Advance 2020 OUT OF STOCK (£2,789.99 at Rutland Cycling), Volt Regent (£2,499 book test ride at Volt), Volt Infinity (£2,799 book test ride at Volt)
Our verdict: The SC-E6100 display, when paired with the E6100 motor gives five assistance levels rather than the three you get with the E5000 motor.
The display is clear and bright and is easy to use. If you buy a bike with a 500Wh battery you’ll get 64 miles of support on the flat on the highest power setting (51 miles and 39 miles, respectively, if opting for a 400Wh or 300Wh battery).
It’s a high-quality motor with incredibly smooth delivery of power to the pedals during acceleration, which is sharp and crisp.
The motor is also quiet. It’s not quite as good on steep hills, and the motor does have a tendency to noticeably jump in and out as it reaches top speed (causing a bit of a yo-yo effect), which contributes to it not getting one of the highest test scores.
Shimano Steps E8000 with SC-E8000 display (300Wh battery)
Range: 65 miles
Our verdict: The E8000 is a very slight improvement on the E5000 and E6100 Shimano motors. It will power you for 65 miles on the flat and an impressive 21 miles on steep hills with a 500Wh battery, making this motor have one of the best miles per watt hour we’ve tested.
This means you’ll get further with this motor than others, when connected to the same-sized battery. The motor accelerates you very smoothly and quickly up to top speed, and it really comes into its own when powering you up either gentle slopes or steeper climbs.
The delivery of power isn’t as smooth as some other motors, particularly on flat terrain, but in general this is a high-quality motor that you won’t be disappointed with. The SC-E8000 display has three assistance levels, but we didn’t find it as clear or easy to use as other displays that are available.
If you’re into mountain biking, this motors acceleration will help you shoot off on even steep hills. But if you want one that overs a bit more support on your commute look for a bike with a higher star rating for flat terrain support.
Suntour R250HP with Suntour ATS display (400Wh battery)
Range: 61 miles
Bikes with this motor include: Carrera Subway E Mens (£1,099 at Halfords), Carrera Subway E Womens (£1,099 at Halfords), Carrera Crossfire Womens (£1,399 at Halfords), Carrera Crossfire E Mens (£1,399 at Halfords), Raleigh Array Crossbar 2022 (£1,595 at Pure Electric)
Our verdict: You can find this rear hub motor in Halfords popular Carrera electric bikes, and it’s not half bad, although it’s not up there with the best.
The range from a 400Wh battery is extensive on the flat and you’ll get 15 miles on the highest setting on a steep hill, too. The motor also accelerates a bike promptly and smoothly up to the maximum speed. It’s when the motor gets up to top speed where the problems lie.
It tends to abruptly cut off the power, which leads to a bit of a yo-yo effect as the motor cuts in and out when you’re cruising at 15.5mph.
The best motots manage this top speed cut-off a little more smoothly. The motor is also a little noisier than most. If you’re looking for cheaper e-bikes with a decent motor, then this one is a good choice, just don’t expect the performance you get from a top brands motor, such as Bosch or Shimano.
How we test electric bikes
All of the e-bike motor systems we test are set up on a rolling road in a lab and put through an array of tough tests designed to simulate real-life use. We use the same setup to test all the different systems, so that you can easily see how they compare.
How we calculate electric bike range
Manufacturers may give a mileage figure on their electric bikes, but they often won’t publish the weight of the rider or the conditions they’re riding in. Trying to compare range with another bike is therefore almost impossible. For our range tests we keep the following constant:
Weight of the cyclist (70kg)
Frontal area and air resistance
Rolling resistance of the tyres
A constant speed of 15.5mph is maintained
when the bike is up to speed
When the bike is on a slope of 6% that speed is reduced to 11.2mph
You won’t find range figures for e-bikes that are truly comparable anywhere else.
We conduct our range and incline tests on three separate power-assistance settings: 100% assistance Motor is putting in the same effort as the rider 150% assistance Motor is putting in more effort than the rider 200% assistance Motor is putting in twice as much effort as the rider
Different cycling terrain
Each e-bike system is tested on a flat road, a shallow hill (1.5% gradient) and a steeper hill (6% gradient). Many of the motor systems we’ve tested can’t provide all of the levels of assistance described above on even a shallow hill, making them unsuitable for hilly areas.
Expert riding assessments
Each e-bike motor system is assessed for the following criteria: The smoothness with which it delivers power to the pedals Some motors are noticeably juddery when delivering power. How well it accelerates from a standing start
Some systems don’t deliver power until after a few pedal revolutions, making it more difficult and less safe for a rider setting off and getting up to speed. Noise Some motors emit an irritating whine, which could be distracting and ruin your afternoon jaunt through the countryside.
The display unit is rated for how easy it is to use, for example switching between assistance levels, and the visibility of the data it displays in various light conditions.