Brompton Electric Bike Review. Brompton e bike

Brompton Electric Bike Review

I feel extremely excited to be able to test and review Brompton electric bike. Brompton was and still is iconic figures in the bicycle industry. They have unique features such as sticking to their roots, full production in the UK, having a very unique frame design which is classic.

Unfortunately, we didn’t see them having a nice electric bike for a long time.

It has different reasons such as lack of a system which can let them keep their classical looks. Thanks to the new system they can keep the looks and produce a nice folding electric bike.


Brompton unlike other folding electric bikes at similar is using a hub motor, And it is a front hub motor.

Normally I am not a big fan of front hub motors as they have a weak grab of ground due to not having a load on top of them. But this is an exception as Brompton has the battery weight on top of the motor. So this system will have a much better grab compared to other front hub electric hubs.

Besides that it has a better weight distribution compared to rear hub motors as motor and battery weight is on the front of the electric bike, drive train and rider weight is on the back.

I guess another reason they use a front hub motor with a front battery is a cabling issue. For folding electric bikes it is hard to have internal cabling due to the folding mechanism. So that all cables need to be routed externally which will destroy the clean and neat look of the Brompton. So they come with a Smart design about it.


Brompton is doing something fantastic and producing motor in-house. This isn’t something I heard before and I appreciate their effort.

The motor is very responsive and has good acceleration but not very good at climbing hills but small wheel size as mentioned compensates it. It has a 25 km/h top speed. It is a 250 w front hub motor.

If you want to learn about differences of motor types and advantages you can check here.


It has both a cadence sensor and torque sensor.

Cadence sensor measures the # of cadence you make and torque sensor measures how much force you apply to the pedals. Their controller get information from both sensors and let motor give support according to that.

In this way, you will have a much better-reacting motor. Also, you won’t see much surges.


Max speed of Brompton Electric is 25 km/h which is around 16 mph.

It has a decent acceleration and top speed. Again people won’t buy a Brompton to break speed records. It is a folding electric bike.

There are other options in the market with higher top speeds or better acceleration or hill climbing skills. If you live in a hilly area then I advise you to go for a test ride before buying a Brompton electric. To check if the motor can handle your weight during climbing.


Brompton has a unique battery position which we haven’t seen much before other than some conversion kits. The e-bike battery is positioned in the front of the electric bike. At first, to be honest, it looked strange and I haven’t seen many designs like that and It isn’t an ideal position for most of the electric bikes.

But after thinking about the reasons why they did it, it make so much sense.

  • If put batter on the back like Tern Vektron, they need to make bike longer. This is a sacrifice of mobility of a folding electric bike.
  • As they use front hub motor, it needs kind of a load on top of it.
  • If use battery on dowthe ntube, then it will block rider from getting on and off.
  • If they use battery inside the downtube, then they need to use a larger diameter tube which will destroy the “classical Brompton looks” which is a big NO for most of us. We love Brompton for their looks and don’t want to change it.

And I am sure they didn’t choose that design at first. As they have a unique battery pack which needs a lot of tooling. I am sure guys at Brompton spend lots of hours and money to develop this battery.

brompton, electric, bike, review

I have to say the battery isn’t a large capacity battery. It has only 300Wh capacity which is below what we see in the market. I wish they have a bigger battery or at least a bigger battery option. Because a hub motor isn’t as efficient as a mid-drive so 300Wh won’t be enough for some riders.

But they offer a 4A charger which can charge your battery two times faster than what is available in the market. So you always have the chance to carry your charger with yourself and can quickly charge your battery.

Another feature which I like is them having a USB charger on the battery. Most of the electric bikes have USB charger on the display as the battery is located far from the handlebar. But Brompton has a USB Charger on the battery and you can charge your mobile phone while commuting. Isn’t it convenient?

And the battery is designed as a bag so it still looks like a regular folding bicycle with a big front bag (except the motor). A major advantage of this design is the convenience in carrying your battery. So many people having other electric bikes drop their batteries while carrying and they need to order replacement batteries. And trust me it isn’t something fun to order it, as it may cost something around 300-750 based on brand and specifications. Due to bag features of the electric bike battery, it is very difficult to drop the battery. So another big plus from us to Brompton.

Brompton Electric claimed to have a range of 25-50 miles. Based on my experience 20-25 miles is pretty ok to do. 50 miles depends on terrain, hills, weight of the commuter and other factors. But with such battery capacity and the motor seems a little bit hard to reach. But all electric bikes max range is like cars. They are calculated based on ideal situations which is rarely the case in real world.


It is a comfortable electric bike and very functional one too. You have chance to carry your kid, attach pannier bags, etc… on Riese Muller. It is a very nice commuter bike. I wish they also have a front basket but what they offer is already very nice.


Not surprising Riese Muller is offering a very comfortable saddle. They are using a gel saddle which is Selle Royal New Lookin Moderate Male.

It is a very comfortable saddle which is important for most electric bike riders. The Royalgel they use inside the saddle reduces pressure points up to 40% compared to regular padding materials.

It also provides a cooler surface which is important for those of us who park our electric bike under the sun. Their cover can reflect sun more than a regular saddle material and can keep the saddle cooler.

It also has shock absorbers which are elastomers. They work both vertically and horizontally. It will make your ride more comfortable when you are riding on uneven roads.

Selle Royal is also water resistance because of their Royal Vacuum Light technology. This technology let them make the saddle 100% sealed.

It also has ergonomic locking grips which add to the comfort level of the electric bike.

I can easily say these features will make your ride more of a joy and lowers the fatigue.


Unfortunately, Riese Muller Homage don’t offer suspension seatpost. But they have both front and rear suspension and a saddle with elastomers which compensate lack of suspension seatpost.

It has 0 offset and Angle of.5°~18°.

It is a lightweight al. alloy seat post which weights only 261 gram.


In this model, we don’t see a chain cover but it has a chainring which is ok for this geometry but I still wish it has chaincover.

Mudguards are very high-quality SKS A65R which are plastic but very sturdy mudguards.


It has a suspension front fork and rear frame suspension. Both of them offer air suspension rather than spring suspension. In this way, they save a little bit from the weight.

The for they use in Riese Muller is SR Suntour Aion Air. It is a high-end fork produced by Taiwanese Suntour. It has external rebound and low-speed compression adjustments.

The travel can be adjusted from 130 – 160 mm. Aion is an MTB fork and for a commuter electric bike, it provides more than satisfactory results. You will have a very pleasant and comfortable ride even on medium level off-road.

On the rear Riese Muller is using X-Fusion O2 Pro Air. This is developed with the help of Brian Lope who is a pro biker. It has a very good bump sensitivity but also very efficient suspension too.

If you want to change the fork travel you can check the below video which is very informative.


Riese Muller Homage has a low step-thru geometry which most of us will appreciate when getting on and off. Especially for those who have some physical problems while getting on and off their electric bike. Not only this Riese Muller offers three frame size for Homage that will make it easier to buy correct size e-bike for yourself.

The only issue I can see is the extra battery (Bosch Powerpack) position. It is a little bit obvious in the middle and when it is mounted it can make it a little bit harder to get on and off. But once get used to it, seems not big of an issue.

Also if you are going to load your e-bike to a car rack don’t forget to remove batteries as your e-bike is already heavy. In this way, you can make it lighter and it will be much easier for you to lift the bike. Also, you can remove the ABUS lock too which will make your job much easier.

Another cool feature is you can still run your electric bike with one battery which can be either Powerpack or Powertube. So if one battery is low on charge and you want to leave at home for charging while you are outside, you are free to do so. This way you won’t need to carry that heavy battery with yourself.


It is a functional electric bike. It has very nice features such as having lock, integrated lights, rear rack, etc…

But I see other electric bikes at much cheaper offering more functionality as a commuter e-bike such as Ariel Rider M-Class or Wallerang.

Again I love everything about this e-bike but at this price range, I wish to see at least front basket as an option.

Rear Rack is very sturdy, nicely designed. Sidebars prevent panniers to touch your gears or wheel. And geometry is very eye-catching and make it possible to use 90% of baby seats available in market.


Riese Muller is using Schwalbe Super Moto-X tyres at 27.5″ dimensions. Nothing to say about Schwalbe as they are very comfortable tires. It offers very high end riding characteristics without sacrificing comfort. It has \3 mm Green Guard puncture protection and reinforced sidewalls make Schwalbe a very durable tire.


If you are a big fan of classic British looks then you will love this electric folding bike. It sticks to it’s roots without giving many compromises.

You can tell it is a Brompton even from a mile away. The same round tubes and frame geometry is kept.

And due to battery position, it can be folded like a regular Brompton bicycle and can keep battery separated from the bicycle. This is very convenient when you are lifting your bike or loading to your car. Also can be inconvenient as you need to remove the battery each time you need to fold the bike.


Brompton Electric isn’t different from other Bromptons; reliable and safe electric bike. Considering the max speed of the bike and motor power they use safety features enough to satisfy any rider.

The tyres have side reflective to increase visibility at night which is a very important factor. As you may need to ride your Brompton at night and you want to be visible even in a dark area.


Brompton Electric has Dual Pivot Hydraulic Disc Brakes with cut off function. In this way when you press the brake the motor will cut support.

Hydraulic brakes are very comfortable to use and reliable. You don’t need to apply big forces to levers when you want a sudden stop. Also as hydraulic brakes have closed system they tend to create less problem as they aren’t affected by dust and dirt as much as mechanical brakes.


It has both front and rear light which are produced by Busch Müller. I love the lights of Busch Müller which are very reliable and good quality lights.

They use electric bike battery as power source and work perfectly.

I just feel battery kind of blocks the lumination of headlight but It is something expected due to the choice of battery position during design. Let’s not forget many electric folding bikes don’t offer front and rear light as standard.


Brompton is famous for high-quality bicycles, classic designs but they are never famous for being “cheap” and the same is true for their electric bike too.

Currently, they aren’t being sold in the USA (at least officially) but in the UK the price of Brompton electric is 2595 GBP which is roughly 3380.

They announce as starting from but I don’t see much options to upgrade the bike or different component packages.

It is an expensive electric bike but you in the end not buying a bunch of components but you are buying the brand, style, history. And also Brompton has a very good after-sales service and they are in the business for a very long time.

So there is a premium for all those extras. If you don’t have financial problems, then the price of Brompton isn’t that unreasonable.


You can check Brompton electric from their website.

Brompton Electric review: E-folding bike with a touch of F1!

The Brompton Electric is a folding e-bike that fits easily into your trunk and weighs less than 20 kg. battery included! A real Formula 1 legend provided enough juice in the electric motor to get it going as well. In this NextPit review, I pulled away not only from bicycles, but also from cars and motorcycles at the traffic lights. Talk about an ego boost! You can find out just how long I was able to keep my nose in front of his detailed review.

Brompton Electric in a nutshell

I don’t think it ever gets boring to ride the Brompton Electric to the front at the traffic lights and pull away from the angry looks that waiting cyclists throw your way at an incredible speed. The fun factor never gets old with this e-folding bike, as you secretly know you’re riding with tires that are far too small. Brompton’s legendary folding mechanism provides all the flexibility you require at just the right weight.

However, Brompton’s folding bikes are already expensive in the first place, which leads to high that begin from 3,800 onward. Having said that, tiny issues like engine failures whenever you’re riding on cobblestone paths become all the more unforgivable. However, commuters who can afford or want to finance the Brompton Electric may simply pick it up for its status symbol. This is especially stark considering how the name Brompton emblazoned across the steel frame is equated to a quality, long-lasting product.

Design and quality

The Brompton Electric is a folding e-bike and can thus be folded to the size of your everyday suitcase. When folded, the e-bike only takes up 65 x 58.5 x 27 centimeters of space, tipping the scales at slightly less than 17 kilograms with the battery attached to the front of the handlebar alongside the carrying bag. Alternatively, there is also a larger bag with additional storage space, different handlebars, seat posts, and a choice of two or six gears.

What I liked:

  • Folding mechanism is lightning fast once you’ve mastered it.
  • High-quality workmanship with cool attention to details.
  • Fits in your carry-on luggage, trunk, or even on the passenger seat.

What I disliked:

  • Small wheels were quite slippery in wet conditions.
  • Handlebar design caused a sore spot on the inside of the thumb during longer rides.

As it is with folding bikes, we always have to distinguish between the unfolded state and the folded state with the Brompton Electric. What is clever with this design is the very first step in folding that involves the rear wheel, which then doubles up as a bicycle stand. It is then the bike will stand on two small wheels, but with a rather small wheelbase, it is not 100% stable, albeit functional.

However, this small wheelbase is necessary in order to fold the bike into a tiny dimension with two more subsequent folding steps. When fully folded, the Brompton Electric is only as big as a suitcase and throughout my review, it managed fit on the passenger seat of a VW Crafter as well as in the trunks of a VW ID3, an Audi A5 Kombi, and a VW Polo. You almost forget just how small it can be when you ride the Brompton Electric.

This is because even without electric support, the Brompton rides very well. If you were to look forward to longer rides, you will forget that you are actually riding on a tiny bike. This is because Brompton managed to deliver an excellent handlebar, saddle, and pedal position that resembles that of a conventional bicycle. The one provided by the manufacturer also came with six gears.

The 6-speed version is more expensive and therefore, adds more weight. Since I only switched between third and fourth ‘gears’ on the sprocket most of the time in the review, I would personally settle for the cheaper option without any hesitation.

Although Brompton relies on high-quality Schwalbe Marathon Racer tires, I felt rather unsafe when riding in the rain. The small tires always felt as though they were about to slip away. While I never experienced any dangerous situations, the engine was powerful enough to spin the front wheel while I was in gear three under wet conditions.

Before we talk about the motor in the Brompton Electric, there are three more things to know: First of all, you don’t look majestic on the folding bike. This is even more pronounced for tall people, which Brompton has taken into consideration with a telescopic seat post and a higher handlebar, making you look a bit like the proverbial monkey on the grindstone.

During my review, however, I decided against letting looks influence the overall score while cycling. On the one hand, I don’t care how I look on a bike as I also ride with a helmet 90 percent of the time (and that alone makes me look dorky), while on the other hand, it’s a feature that all folding bikes have in common.

On the other hand, Brompton’s bikes are known for their durability. Even with the electric model, the manufacturer uses a steel frame which does weigh it down a bit. According to the manufacturer, the manufacturing quality standards are so high that there are specialized employees who do not weld the steel parts together, but rather, solder them.

Last but not least, one more criticism concerning the bike’s design: On long rides, I always ended up with a sore spot on the right side of my thumb because the skin on that part kept on getting scraped at. Perhaps I’m just as delicate as a pretty butterfly.

TL;DR: The Brompton gets full marks for design and quality. To criticize it for not looking elegant while riding a folding bike is difficult. This is because that is something you have to live with when it comes to folding bikes right from the very beginning. It is more about the practicality and riding experience, and those are departments where the manufacturer really gets everything right.

E-motor and driving fun

Brompton purchased the Williams Formula 1 and has used the latter’s expertise to develop its very own motor for the electric bike. The motor has a power of 350 watts and is adjustable in simple three steps and via a bottom bracket sensor. According to the manufacturer, the motor has been optimized to cause as little resistance as possible without any further assistance required. I must admit, this undertaking has proven to be rather successful.

What I liked:

  • Motor provides an enormous boost.
  • Sensor in the bottom bracket is very precise.
  • Control in three stages proved to be extremely useful.

What I disliked:

  • Motor cuts out if vibrations are too strong.
  • Companion app is only available for iOS until the end of 2021.

Brompton has placed the electric motor in the front tire. It looks a bit like a conventional hub dynamo that might be power your bike’s lights when it gets dark. The position in the front wheel makes you feel like you’re being pulled rather than being pushed. After the press bike tour organized by Brompton, I still had the feeling of being pulled forward even after dismounting. One participant described a similar feeling to me when asked. However, it takes just a few rides to get used to such a feeling.

What you won’t get used to is the joy you will feel when you engage the Brompton Electric at traffic lights. The motor has a power of 350 Watts and offers even more power than the VanMoof S3 (250 Watts). By the way, over in Germany, the maximum power rating for e-bikes stands at 500 watts. Here is another tip from a racing pro: The second gear on the right thumb and the third support level are the best mix to help you pull ahead of the pack quickly. This way, you will leave all the other cyclists behind. as well as cars and motorcycles eating your dust (albeit for a few meters) with a little effort.

Gradients and strong winds do not pose to be a challenge with so much power at your disposal. If you prefer to take it easy, you can achieve a very balanced riding experience with one of the lower gear levels. It is then the motor does precisely what it was designed for: to support you while cycling.

In Berlin, however, it fails in its job when the going gets bumpy or rough. Apparently, the Berlin city center consists largely of ancient cobblestone paths and due to the strong vibrations, the motor often failed to work. The reason behind this? Brompton hooked the battery via a vertical holding mechanism on some contacts. In doing so, the amount of vibrations it receives is probably too much, that the battery automatically switches off for your safety. To remedy this inconvenience, I had to remove the battery completely at times.

By the way, the bike does not offer so-called regenerative braking, i.e. charging the battery while braking and idling. In this regard, the manufacturer told me that calculations involving regenerative braking for the battery when it comes to e-bikes is different from those in electric or hybrid cars. The additional weight compensates for the gain in battery power, but because of the weight, you still end up with a net loss in power.

The companion app, which shows your speed, provides an overview of the service history and other information, and is only available for iOS as of August 2021. There will be an Android version coming later this year, according to Brompton’s PR agency.

TL;DR: Besides its portability, the fun factor is a real reason to buy the Brompton Electric. The bike lurches forward in such a manner that you can do nothing but smile during the first few rides. Only when the motor fails on cobblestones and app’s availability on iOS are the only two drawbacks, in my opinion.

Battery performance and durability

The battery of the Brompton Electric resides in a bag that is attached to the front of the handlebar. This is a practical design when you fold the bike as you either have a counterweight on the arm that does not carry the bike, or you can sling the bag over your shoulder. The 70 km maximum range certainly makes it stand out from other e-bikes.

What I disliked:

  • Charger can be a bit fiddly.
  • Only certified workshops can repair it.
  • Many parts are custom-made.

Brompton stated the range of the 300 watt hour battery is anywhere from 30 to 70 kilometers, depending on the level of assistance and condition of your bike route. If you’ve already read my earlier observations concerning riding fun, you would know that it was closer to 30 km for me. During the review period, however, I only ran out of juice only once. And that was a good thing, because it allowed me to discover two other important things:

Firstly, riding without a battery is still a pleasant experience, as the motor actually offers very little resistance. Secondly, the very good and bright light still works when the battery is empty. which means you can still get around safely in the dark even when you are all out of juice. This is definitely a positive surprise that I had not even thought about before the battery ran dry.

The 70 km range stands out compared to other e-bikes in the market. The VanMoof S3 touts a maximum of 60 km alongside the Sushi Bike, while the Cowboy Bike 3 is able to achieve what the Brompton Electric can in our e-bike comparison. We must also remember that you will often use the Brompton Electric more as the last mile ride.

Hence, you can cover distances of up to 35 kilometers from the train station to work every day, leaving in the morning and returning home in the evening comfortably. If you plan for longer routes, you can still take the Brompton Electric with you on public transport without having to pay extra.

The charger which you have to plug into the back of the battery bag, unfortunately suffers from a drop in quality compared to the rest of the bike. It offers some LEDs for information, but does not show the remaining charging time.

Charging time can be rather long at four hours in total and unfortunately, I discovered that the battery was not charged the next morning despite leaving it plugged in during my review period. and this happened twice! The reason behind this? You must first place the charger in the wheel and then plug in both together into the socket. Practice makes perfect, but still, it can be annoying.

Brompton still offers a quick charger, which halves the charging time to two hours.


The Brompton Electric receives an additional plus for its durability. And there is a very simple reason for doing so: many bikes in the city are plagued by rust when left outside to be battered by the elements daily. With the Brompton Electric, you can easily take the folding bike into your flat. The backyard of my apartment has many bike racks without a roof and I never take my heavy 0815 bike upstairs. It’s simply too cumbersome and takes up too much space in my apartment.

Brompton also produces each bike by hand in a factory in London. According to Brompton, high-quality materials should easily ensure a lifetime of over 20 years. Whether the battery will last that long, however, is a questionable affair for the electric model. What’s also exciting is the value of the bikes that tend to remain stable over time without suffering from too much depreciation.

TL;DR: For the infamous last mile travel, the battery life of the Brompton Electric is entirely sufficient. However, only 30 kilometers are possible when the weather is hot, and also do take into consideration the rather long charging time of four hours via the included power adapter. For an additional money, however, there is an optional fast charger that reduces the charging time to two hours.

How and where do I buy the Brompton Electric?

You will only be able to find Brompton bikes if your bike dealer is an authorized dealer. Therefore, I have included this short segment in the review, where I will break down the different pricing tiers and purchase options for the Brompton Electric. Let’s begin with the cold, hard facts: How much do you need to budget for if you’re interested in picking one up?

Depending on where you live, certain dealers might provide the right kind of financing plans to suit your budget. Do take note that Brompton does not offer any options for leasing.

Do you want to talk to a bike dealer about the options or ride the tested e-bike yourself? Then you can locate a local branch via the Brompton website which will show you all authorized dealers in your area.

Brompton Electric technical specifications

The folding mechanism is extremely easy and becomes second nature after some practice, allowing you to fold and unfold the bike in under a minute. Although placing the battery in a handlebar bag is a handy move, Brompton needs to come to terms with connectivity issues where strong vibrations are concerned, as that is one of the very few things that wasn’t fun about the e-folding bike during my review run.

Last but not least, this could also boil down to the fact that the bike was loaned to me for free. To fork out close to 3,800 of my own money would certainly change the way I look at it in a review. The Brompton Electric is very expensive, as anyone who were remotely interested in it balked when I informed them of the price during the few weeks I rode it.

brompton, electric, bike, review

However, I still don’t think this price is unjustified and over a period of 20 years, you can say that this is a very good investment to consider.

Disclaimer: Brompton invited Nextpit on a bike ride at the beginning of the review period and bought me drinks and food. The benefits provided from the outdoor press trip had no bearing on this review.

Brompton Kit

Brompton’s are among the most exquisite of compact folding bicycles, but also among the more challenging to convert cleanly into electric assist. The front fork uses tiny 8mm dropout slots and a narrow 75mm hub width, the rear tire folds into the bottom bracket eliminating most mid-drive options, and the triple fold adds challenges to the cable routing and component location. But once properly outfitted, they make excellent electric bikes. Portable, compact, easy to travel with, and a delight to ride.

We’re happy to offer purpose built conversion kit packages tailored for this bike for the discerning enthusiast, with 2 motor sizes and a range of control options. Please note of course that Brompton does not endorse any 3rd party modifications to their bike and will be quick to point out that electrifying your Brompton bike will void your Brompton warranty, as is their right. Of course it is your right to do what you like with a product that you purchased and own, and we’re here to help you have fun with that.

Motor Choice

At the moment, we have two hub motor options for the Brompton forks: a small 1.8kg geared SOFP motor, and the larger Crystalyte SAW20 direct drive motor.

SOFP vs SAW Comparison

Weight 1.8kg 3.2kg
Diameter 144 mm 184 mm
Motor KV 13.4 RPM/V 13.6 RPM/V
Phase Resistance 0.182 Ohm 0.24 Ohm

The geared motor is recommended when you want the most discrete package, when weight is a top priority, or when you want a motor that freewheels with zero drag when pedaling without assistance. It offers decent power levels (upwards of 500 watts) and can climb hills pretty well, but being a geared motor it also some audible buzz and it can’t do regenerative braking. The SOFP motor option is discontinued as of 2023.

The Crystalyte SAW20 motor is ideal when you want the fastest and most powerful setup and aren’t quite as concerned about motor weight. Being a direct drive motor it is totally silent when running and can also do regen braking, which is a great feature on bikes like the Brompton that only have rim brakes available. It’s also more ammenable to running at high system voltages with Statorade cooling, as we demonstrated here.

Full performance under different load conditions is available from our motor simulator, by choosing the Clyte SAW2013 or Brompton SOFP options from the drop-down list, and creating a 16.7 custom wheel size.

Display Options

You also have the option to choose whether you want a comprehensive V3 Cycle Analyst device or a simple 5-LED display console.

The eZee LED console gives a basic indication of your remaining battery charge, and the up/down arrows let you set 5 different power levels. It is a great option for an introductory throttle controlled ebike setup where a simple non-technical display is all that is needed.

The V3 Cycle Analyst has a much more complete technical readout of your speed, battery voltage, amp-hours used etc. With the V3 Cycle Analyst, you can not only tune your throttle behaviour, you can also configure the bike for automatic pedalec assist modes with a PAS or Torque sensor so that you don’t need to press a throttle for power.

brompton, electric, bike, review

Pedalec Modes

If you opt for a V3 Cycle Analyst display, then you have the option to add pedalec control of the Brompton without needing to use the throttle for power. Both the simple PAS sensor and the more elaborate torque sensors can reduce thumb fatigue while riding and lead to a pleasant automatic assistance.

The 12 Magnet PAS sensor installs on the left crank and simply senses when you are pedaling. You then configure the Cycle Analyst to put out a baseline power whenever you pedal, and use the throttle for when you want to override that with manual control.

The torque sensor takes this up a notch by sensing not just cadence, but also the force that you are applying to the pedals. This allows the Cycle Analyst to regulate the motor power in proportion to your pedal effort. As you ride harder, you get more assist. However, the installation of the torque sensors is considerably more involved than the split disk PAS sensor, involving a replacement of your bottom bracket and (in the case of the ERider device) your crank arms. We only recommend this option to those with greater familiarity with bike mechanics.

Other Accessories

There are a few useful accessories that aren’t part of the kit bundle on the store site but which can be worth adding separately to the order.

  • Headlight: Both the eZee LED meter and the Cycle Analyst include a DC power plug bringing out your battery voltage to run a front light with no extra wiring. The Cycle Lumenator casts the brightest beam while the potted Electrolights can mount cleanly under the Cycle Analyst with a long bolt through the enclosure.
  • Ebrake Cutoffs: We don’t recommend to bother installing ebrake cutoffs with small geared motors, but on the direct drive SAW20 motor this is a great With the 20A Grinfineon and Baserunner controllers you can add any of the ebrake cutoff levers to the order if you want to have regenerative braking whenever you squeeze the brakes. We don’t include brake levers in the kit because for most people it’s easiest just to keep the original levers fitted on the bike, but if you want them they are available here.

The Brompton M6L Electric is a premium folding e-bike

TechRadar Verdict

This neat variation on the iconic Brompton folding bike design offers a premium pedal power experience that’s all the more impressive thanks to battery assistance and a hub motor. Manufactured to a high standard the Brompton M6L Electric boasts some clever features, but comes with a sizeable asking price.


  • Ingenious folding design
  • Built using quality components
  • Deceptively zesty performance


  • – Premium but expensive
  • – Folding it up takes practice
  • – Not the heaviest but still weighty

Why you can trust TechRadar

We spend hours testing every product or service we review, so you can be sure you’re buying the best. Find out more about how we test.

Two-minute review

Brompton is a British company that’s been making its pedal-powered folding commuter bike for nearly 50 years and business still appears to be brisk, even though less of us are actually commuting to places of work. Perhaps its because so many of us don’t have much space to store a conventional bike, which makes a folding one a practical solution.

However, Brompton has also decided to bring a battery-assisted model to the e-bike marketplace, after developing an innovative hub motor design in collaboration with Williams Advanced Engineering. Working closely with engineers noted more for their experience in Formula E has produced a folding electric bike that might not have race car appeal, but does deliver a zesty battery-boosted riding experience. Alongside the nippy performance you get an agile little bike that oozes quality, while retaining the quirky charm of the original Brompton design.

Having a battery on-board does add weight but, ultimately, this is still one of the best commuter cycles you can buy, which is also reflected in the price. Spend some time picking a tailored specification from the range and it should be a good fit for most riders.

Price and release date

The Brompton Electric was first launched in 2017. start at £2,725 (about 3,700 / AU5,000), and the bike tested here retails at £2,850 (about 3,800 / AU5,200).


The Brompton folding bike is an instantly recognizable sight and it’s good to see the company moving with the times and creating an e-bike edition. While it might not have been the first electric folding bike to come to market, the development time has been spent wisely.

The M6L Electric carries many of the same design characteristics as its traditional counterpart, but there are subtle differences. Central to the bike is, of course, its folding capability and this works just as well as it does with a regular Brompton.

If you’ve never been through the process of folding or unfolding a Brompton then it might not be immediately obvious how this process works, but a little practice and it becomes satisfyingly fluid. Granted, with the M6L Electric there’s some additional baggage to consider, namely the 36V battery pack complete with a USB port, which sits under the handlebars.

There’s the front wheel too, which has the hob motor assembly that provides the power to help pull you along when the battery is switched on. It all adds weight, meaning the steel-framed M6L Electric is 18.4kg and while that’s less than rival models, like the decidedly heavy eTrends Fly, it’s a point to ponder over if you’re faced with lugging it over bridges at stations, finding a spot for it on the train or hauling it to and from the car park during rush hour. Two little wheels incorporated into the design do allow you to trundle it along folded though, albeit precariously.

Nevertheless, Brompton has done a fine job with the overall look of the bike with an upright riding position provided by an extendable post for the fairly uncompromising saddle, complemented by workmanlike handlebars. Fully extended, it’ll accommodate an inside leg measurement of 33-35 inches.

Mudguards cover the Schwalbe Marathon Racer tires, with their reflective strips, while a 40 Lux Busch Muller and rear Spanninga Solo XE lighting setup ensures you can see and be seen.

Our model came with six gears, though there’s a slightly cheaper two-gear model available. Brompton’s Essential bag for storage comes with the bike, while a larger City option is available to buy. There’s no kickstand unfortunately.


The M6L Electric offers a perky riding position once you hop on board, with the saddle and handlebars offering you a lofty position above the bike. Power for the battery and the assistance that comes with it can be configured before you set off as the controls are on top of the battery pack, with power, mode (1-2-3) and light buttons at your fingertips. It’s not a big deal, but some sort of control on the handlebars would make the experience even better.

Push off down the road though, and the ride is classic Brompton, with the small wheels delivering a surprising amount of agility in tandem with the practical handlebar arrangement. Using pedal power alone the bike does suffer from having that extra weight, but call upon the dynamic hub assembly on the front wheel to help you out and the M6L Electric fair zips along.

The experience is a little different to electric bikes powered by motors at the bottom of the frame, or those with rear-mounted hubs. You feel like you’re being pulled along and it’s a lot of fun. Given that the M6L Electric is meant for shorter commutes it actually feels like it wants to keep going.

According to Brompton the battery range is 20-45 miles, although after the hilly workout we tried it on for the first run the power pack showed it was suffering from all the help it was giving. For city or urban streets however, the M6L Electric has the potential to match that official figure. The balance seems to be to use the power as a supplement, as opposed to letting the bike provide the bulk of the assistance.

Once you get in tune with the way the front hub ticks the end result offers up a really pleasing mix of performance and enjoyment. Run down the battery and Brompton says you’ll be able to recharge the battery in around four hours with the standard 2A charger. A faster 4A charger option is available to buy, which cuts the charge time in half. Normal use, however, should mean an overnight boost to the battery pack will be perfectly fine though.

Once you’ve got into the swing of things the Brompton M6L Electric rewards you with versatile performance, with those three levels of pedal assist designed to suit different riders and gradients. Luckily you don’t have to pre-assign the assistance mode as it can be done on the move, but it’s not the most intuitive of systems.

To make this e-bike really good, Brompton could pull off a masterstroke could integrate the mode-changing ability onto the handlebar area. The power delivery curve is perhaps something else Brompton could do with looking at as it’s not always as smooth as you’d like, even though it’s possible to reach the standard 15mph or so limit for an e-bike at the end of it.

There are one or two other minor irritations too, with the battery pack rattling around a bit on our unit. Fatigue sets in a little if you’re on longer runs too, mainly due to the saddle. However, the Brompton M6L Electric is a commuter bike, so you can’t really fault it for those shorter jaunts.

Buy it if

You need a commuting solution The Brompton features a tried and tested design that makes it ideally suited for anyone taking on the daily grind.

The Brompton Electric Is the Most Functional Folding E-Bike We’ve Seen

The takeaway: The best folding commuter bike is about to get better.

  • Who should ride it: Commuters who want to show up to the office sweat-free and stash their bike under their desk.
  • What welove: The super-smooth proprietary motor.
  • Something wedon’t: It’s not currently available in purple metallic paint.

Price: 3,499Weight: 32 lb.

From Bicycling

Update: On March 21, 2022, Brompton announced a voluntary recall of this Brompton Electric model to address an issue where, in certain circumstances, an object can become stuck between the mudguard (fender) stay and the tire. This can then result in the mudguard becoming stuck in the tire and causing the wheel to suddenly stop rotating. Brompton is replacing, free of charge, the mudguard stays with a new version that has more clearance with the tire.

Additionally, Brompton announced an update to the battery catch to reduce movement between the battery and the bike. Brompton states “This minimizes battery disconnections, prolonging the life of the electronics and improving ride experience.”

To check if your Brompton Electric is affected by this recall, check out the Brompton website where you can check your bike’s serial number, watch a video on the issue, and get more detailed information on this recall.

Brompton bicycles meet the needs of their intended users perhaps better than any other bike on the market: Commuters with a short distance to ride to work and people who take the train and use the bike for their first and last mile. The Brompton Electric, therefore, took a great tool and lessened the rider’s need to shower upon arrival. Its 16-inch wheels give it great off-the-line and uphill acceleration, and the e-assist is smooth and gradual. An internal torque sensor in the bottom bracket communicates with the front hub motor to conserve battery power. When the motor tops out or senses low torque, the bike rolls along on your power and momentum on the freewheel hub inside the motor.

The internally geared motor offers a maximum assistance of 15 mph. Like all Bromptons, the Electric folds in thirds. It’s available in 2- or 6-speed options, and the frame comes in black or white. Buyers choose between two different handlebar heights: standard, or two inches taller for a more relaxed position. The bikes will go on sale in the U.S. in June or July, says Brompton.

The Motor

Instead of outfitting a Brompton with pre-fab e-bike parts, Brompton enlisted the help of the Formula 1 veterans at Williams Engineering to create a Brompton-specific motor system. The bike employs a 250-watt internally geared motor in the front hub. The small motor uses a relatively lightweight battery, keeping the weight down and complementing the accelerative 16-inch wheels.

The motor has an integrated freewheel for smoother assistance engagement and resistance-free rolling in “off” mode.

A torque sensor inside the bottom bracket communicates with the motor based on your wattage and cadence. The freewheel hub allows you to ride with the motor off and not work against any extra resistance. It also helps save battery power by allowing the bike to cruise under your momentum and lighten the load on the motor when you’re not putting a large amount of torque into the pedals. The transition when the motor engages is smooth yet powerful, and the torque sensor accurately detects when you need a boost and when you’re just cruising.

The Battery

The Brompton-specific battery pack sits on the front, connected where the basket or bag attachment goes for non-electric Bromptons. It’s attached via a jiggle-proof plug that won’t come undone if you rattle over some big potholes. To remove the battery from the bike, press the release button on top beside the handle and lift it off. The battery charges in four hours.

When you turn the handlebar, the battery pack stays in place rather than rotating along with it, keeping the front end balanced.

The top of the battery pack holds an operating pad where riders can turn it on, check the battery level, toggle between four power modes (off, 1, 2, or 3), and switch on the headlight. Buyers can choose between two battery bag sizes. The smaller option holds the battery and has a with enough room for your wallet, keys, and phone. The larger option is big enough to carry your lunch and gym clothes, or even a second battery if you’re headed out on a longer trip. Riders who want to upgrade to a bigger bag up front can order the large bag aftermarket without buying another battery.

Commuter-Specific Design

The Brompton Electric is built around the same frame as the current standard Brompton and is available in black or white. It folds in thirds so you can stash it in a closet, under your desk, or even an overhead compartment of an airplane. This version also comes with mudguards and a bell.

The only user interface on the Brompton Electric is the button pad on top of the battery pack. This sleek design keeps the setup simple for commuters who are merely concerned about getting where they are going and enjoying their commute, rather than keeping tabs on time, speed, or power.

To compensate for their 16-inch wheels, Bromptons come with an oversized 50-tooth chainring. Because smaller wheels accelerate quickly but are harder to get up to higher speeds, the chainring allows riders to go much faster with fewer RPMs.

Brompton designs and manufactures all of its components in-house to make sure they’re optimized to their small frames and unique folding design. So in addition to all the motor-specific parts they design, the touchpoints, rim brakes system, and drive system are proprietary too. Well-executed, utilitarian, and sleek, the Brompton Electric is ideal for commuters who need a fast, no-frills solution to get where they need to go—and want to look good doing it.

Riley is a writer and outdoor adventure guide currently based in Tucson, Arizona where she leads mountain bike rides, rock climbing, and hiking trips. In her spare time, she writes stories and reviews outdoor and fitness gear. Find her writing in publications including Outside, Lonely Planet, SHAPE, Bicycling, Runner’s World, and others. When she’s not playing in the mountains, she’s probably laying down somewhere or eating (or both).

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