I love riding my Brompton in Barcelona and other places when we travel. In fact, I’ve taken it with me all over Europe since it’s so easy to travel with it, whether it’s by plane, train or car.
It’s a great means of transport, but it’s also true that if you live in hilly regions it can be a challenge to use it on a daily basis as a means of transport. The same thing applies if you’re not that young anymore and don’t have the same energy and stamina as before.
Enter electric bikes. They’re not a new concept but recent advances in battery size and capacity, as well as electric motors, have really made possible and driven the market for electric bikes.
The official electric Brompton is now a reality and has been selling like hot cakes. There are however several alternatives that don’t require you to buy a new bike but just convert your existing one.
In this post, I’ll summarize the options available, and continue updating it with new developments as they happen.
I own several Bromptons, and have also bought the official electric version which I love.
So without further ado, here are the current options. I’d love to hear from others who have already purchased such kits or the official electric Brompton and hear about their experience.
Official Brompton Electric Bike
In 2017, an Official Brompton Electric bike was finally released. In my opinion, this is a bit of a disappointing effort, especially given all the years it’s been in development and the hype about it being co-developed with Williams F1.
User reviews are good, and it’s true that works fine and makes certain rides possible that previously were not even contemplated with a manual Brompton.
However there are certain things that could have been done better. I find the price a bit exaggerated, considering it’s around €2,000 more expensive than the manual version. I picked up mine on the second-hand market at a huge discount and it had barely been used.
The electric Brompton is not compatible with the Bobike Mini One child seat that I like to have mounted on my bike. Since getting some help when riding up hills with my son is one of the main use cases for an electric Brompton in my case, this reduces its usefulness. On the other hand, when my son is older he can ride on another seating version, so it’s a temporary problem.
I don’t like the fact that you can’t use the standard Brompton bags either, although the new bags that also carry the battery are pretty nice. I have both versions of the bag and use them both.
On wet days going uphill it can easily spin the front wheel especially if its set on maximum assistance. The fact that you can’t switch the level of assistance comfortably from the handlebars is also an annoyance.
Having said all that, I still love my electric Brompton and use it on almost a daily basis for my office commute. I also like to use it for touring when I’m leaving from my home to go and explore some faraway place. I turn down the assistance but it gives me the peace of mind that if I get too far and need to get back home quickly or I get insanely tired, I can always turn up the assistance and get home in half the time.
So I’ve talked about my gripes and the fact that I still love my electric Brompton, but there are alternatives to electrify your Brompton. Let’s have a look at them.
Swytch Conversion Kit
This started out as a Kickstarter project for regular bikes, but it is now available for many types of bikes including the Brompton. The Swytch Brompton Electric conversion kit probably the most affordable one available at the moment and you can also install it yourself if you have some know-how.
This company is strong on marketing, and ultimately the kit works in a similar way to the Brompton official electric bike. However, you can fit a child seat at the front which makes it a better solution for me. It also looks neater in my opinion. The disadvantage is that it usually out of stock and that it uses a front-wheel driving mechanism, which can get a bit tricky to manage in wet conditions.
ARCC Innovations Brompton Retro Fit kit
The ARCC e2-pod Intelligent Power System is available for the iconic British manufactured Brompton folding bike and can be fitted to all current and older Brompton folding bicycles.
The system allows the bike to be used with and without the currently available Brompton bag systems. The bag can be easily removed leaving the pod attached to the bike.
The ARCC Intelligent Power System has been designed by ARCC Innovations to provide unique intelligent bike power. It combines variable power levels with automatic hill/gradient compensation and launch control. This allows commuting cyclists to choose the amount of effort both they and the motor provides; automatically compensates for hills and gradients; and provides ‘launch control’, for safety when moving away from traffic lights and crossings in heavy traffic.
The Brompton equipped with the ARCC e2-pod Intelligent Power System is ideal for commuting or fast on road riding, delivering a well-tuned, responsive ride everywhere you go.
The big disadvantage here is that this company only ships to the UK.
Brompton retrofit price from £1799
Pendix Electric Assist
The Pendix electric assist kit is a neat German-made system – it’s a crank drive kit, but unlike most crank drives, it can be fitted to conventional frames with no modification. The battery fits to a holder that fits to the bottle bosses or other convenient mounting points. A simple control knob on the battery sets the power output, and that’s it – it’s beautifully simple.
Because of this, it’s perfectly suited to bikes with hub gears, recumbents or any bikes where a hub motor won’t fit.
Since it is a crank drive, it will work on any Brompton – no need to change brakes, wheels or gearing, no frame modifications are needed. This makes it pretty convenient.
I’ve tried a Pendix mounted Brompton and the power delivery was quite natural and probably better than the systems mounted on the front wheel. However, it adds a lot of bulk to the crank and frankly it felt like the Brompton was no longer a Brompton but a Frankenstein bike. The battery also rattled around which added to that feeling of Brompton’s elegance being completely lost.
Note that one big disadvantage of electric Bromptons is that you can’t take them on a plane due to airline restrictions with bigger batteries.
What are your thoughts on the electric Brompton? Would you buy an electric conversion kit for your Brompton?
Hey Jean, do you have any recommendations for a kit for someone in Barcelona?
Does anyone have any feedback on the Swytch system for a Brompton?
I keep updating my on line request for one, but it’s never available – either there is an extreme high demand or there are production problems .
Late reply. I have fitted the swytch kit to my 30yr old bromi. Easy fittiing and i am extremely happy with it. I used to only use the bromi for my train /cycle commute to london much preferring my gravel bike for anything else. So after retiring I rarely used the brommi. Now with swytch I use it all the time and my bigger bike only gets used for long rides. I have the small 5ah battery and have dialled down the power by about 40% and then only use the lowest of 5 power settings most of the time as i dont need all the power and the battery goes further. 20 miles might use less than 1/2 the battery on an easy trip. 99% happy (1% taken off as the motot makes a v slight noise)
Has anyone received a Brompton conversion kit from Humancycle.cc yet. I’ve paid a lot up front months ago and had no reply or delivery to date. Is it a genuine Company ?
Thanks for your report Jean. Can you say more about the Pendix please? Was it powerful (Pendix say their new motor is 63Nm)? Noisy/quiet? Crank motors are theoretically the best place for a motor but you said you didn’t like it. It’s quite a lot heavier than the Brompton Electric.
I have had the Brompton Electric for 2.5 years until stolen last week. I am thinking about my options. I loved, and did have to replace the motor which happened speedily under warranty. My dealer tells me that on later models the issue that required some motors to be replaced has been sorted. Their app is now out for both iOS and Android, and judging by the frequent surveying of users Brompton are keen to develop the app and the bike further. I may just get another! .
Peter
Thank you very much for your article. I am looking for the best solution to electrify a Brompton to a friend of mine. I will contact the manufacturers to import one sample to Brazil. In your opinion which electric assist kit is now the best to a Brompton? Could you please copy and paste the link of the manufacturer homepage?
Hi guys, any reviews and comments on the Humancycle.cc solution? It looks very neat. Also not very cheap and its a company from the UK.
Do you have any views on the Cytronex system?
https://ebiketips.road.cc/content/reviews/accessories/cytronex-brompton-2379
Many thanks.
I have had a standard Brompton for 20 years. Living in a hilly city in the U.K. and with a knee issue I bought a Brompton electric….absolutely brilliant. I use it most of the time and often quicker than a car. It is expensive but worth the money.
I recently purchased the OneMotor friction drive conversion kit for my Brompton SL6 (Black edition) from https://onemotor.co. I looked at the comments section here before deciding which Brompton conversion to buy and noticed a comment about the OneMotor which sounded intriguing. After researching a bit more, I took the plunge. As a UK purchaser buying from the USA, that was a big step, but after two weeks with the motor, I have absolutely no regrets.
The conversion was easy to install. It took me about 30 mins with standard tools. The components are beautifully engineered to fit the Brompton perfectly. This is a friction drive which sits above the front wheel. To create space for it, you are provided with a specially designed luggage block that lifts the luggage clear by a couple of cm.
The motor is also very easy to use. There is a wireless controller (an option but essential in my view) which gives you a lot of information about battery life, range, level of assistance etc. The settings for the motor can be controlled through the controller or your mobile phone via an easy to use App (or even via the pedal assist sensor). One of the great things about the OneMotor is that you can set the power output according to the law of the land. So whilst it is set for use in EU (250w, 25kph max assist), you can also set it to US mode or Canadian Mode. In US mode, you would have a whopping 750w at your disposal with a max speed of 40kph! I’m not suggesting that you should use anything other than EU mode when using it in Europe but it is nice to have the flexibility should you take your Brompton (or any other bike – see below) outside the EU or off-road.
Now, the OneMotor is not cheap at around $1,400 (plus import duty), but that compares reasonably with other kits mentioned by Jean. More importantly, what you get for your money is not just one conversion but a kit that can be used for all your other bikes too. Just remember to order some extra mounts for your hybrid and/or your road bike and you have three electric bikes instead of just the one. It takes moments to take the motor and battery off one bike and attach it to another. I purchased two additional mounts so the way I look at it is that I got three conversion kits for $500 each. That is a pretty good deal.
As for performance, I have a 30km commute to work, which before Covid-19 was a bike-train-bike journey with my Brompton. Now with the restrictions on travel, I decided to cycle all the way. But there is one problem, which is a 4 km climb of about 200m half way. I can do it without the motor, but at my age (let’s just say I am 50++) a bit of assistance is more than welcome. The OneMotor works really well. Even at a medium power level on the EU setting, I can easily get up the short 10-12% sections of the hill with the same effort as if I was going up a 3% incline.
The standard battery has a stated range of 16 – 32km. Obviously you will not get that range if you have a high setting on and are climbing all the way. But it was enough for me to cover 30K with a few hills. I mainly kept it off on the flats to conserve power, and because I only want assist for when I need it. It is worth mentioning that when you do switch the motor off, it retracts off the wheel completely, so you have no drag. And, in case you are wondering, I have ridden when it’s wet. I expected the motor to slip but there are some clever electronics that enable the motor to sense slippage and apply more pressure for traction. The result is that the grip was still pretty good.
Anyway, that’s enough from me. Just to confirm, I have no connection or affiliation with OneMotor. I am just a happy customer and wanted to share my thoughts. I may update once I’ve tried the machine out on my road bike. If, like me, you love your Brompton, but also have other bikes that could do with electrification, then this could be a good option.
Hi, how much did you pay for the import duties, taxes, transfer fees + shipping etc.
I live in London and I am interested in the onemotor kit for my H6L
Thank you
I have a Brompton fitted with a Crystalyte motor (Crystalyte Europe in Belgium, see website:
http://shop.crystalyte-europe.com/product.php?productid=16694&cat=327&page=1
and very pleased with the performances (amongst it a range of +/- 28 km without pedalling)
Did you get the NSM Light weight motor or the SAW20 High torque ? Any thougth about torque?
Was it easy to install ?
The motor that was mentioned in my post and link of course. Not that difficult to install.
Met vriendelijke groeten, Bart Sabbe – Oostende – Belgium
Hey, which other components do you have, controller and battery pack, etc? I am trying to combine my kit from scratch but am having troubles – any help is appreciated 🙂
Ana
Ana,
Where are you from ? Ask Crystalyte if they have somebody distributing their products in your area.
My kit is motor as mentioned + controller.
Batteries are Chinese and they are as good as any other European or American battery.
Kindly yours,
Thank you, Bart. I’m from Europe so no issues there. One more question if I may – is there any “drag” or resistance when pedaling without assistance or is it smooth?
Thanks again
Ana,
Sorry for my late reply. I ‘m abroad on holiday (La Gomera, Canarian Islands) at this moment (with a non electrical Brompton).
No there isn ‘t any “drag” or resistance as there is for example with a dynamo on a normal bike.
Sometimes there are Crystalyte electrical bikes available for sale on tweedehands.be (second hand website in Belgium).
I know a guy who owns one and who might be interested to sell it second-hand.
His emailaddress: [email protected]
Give it a try and who knows.
Good luck, Bart Sabbe – Oostende – Belgium
Great article Jean. I wanted to share our new product with you, as it also offers a wonderful Brompton electrification option:
https://onemotor.co/
OneMotor can add electric power to ANY bike, MANY kick scooters, and even the bike share systems in 20 cities. And it’s removable in seconds, reassembling to a small package you can carry with a handle (great for locking up!).
It’s ultra-light (4.5lbs/2.0kg with the Compact Battery Pack), high power (750W in US / 250W in EU) and high-speed (28mph in US / 25kmh in EU), and features both a Wireless Controller AND a Wireless Pedal Assist Sensor.
And indeed OneMotor works perfectly on a Brompton – it’s fully compatible with the front luggage system and it doesn’t interfere with the fold at all when installed (and of course you can remove the entire thing in seconds).
We’ve taken the old technology of friction-drive and elevated it to modern performance with our patented Automatic Traction Control system. It lifts off the tire automatically when not in use for zero drag, and it continuously adjusts pressure of the drive motor on the tire (via a secondary motor) in response to changing surface, tire, and weather conditions.
OneMotor is really a unique solution as it’s the only product in the world that can power bikes and scooters interchangeably. Not to mention bike share bikes… And for Brompton riders it’s the ideal lightweight solution, particularly if you have more than one bike and/or kick scooter (which many of our customers do).
OneMotor is now shipping direct both to US and EU customers and we expect to have EU distribution at some point in the future. Happy to answer any questions folks have here, or email us directly at [email protected]
hi jean! any news of any reasonable and working kit for a brompton?
As you can see there are several options now, although in my opinion it’s still early days. The official one is too expensive for my tastes (given that it is fairly new technology that will likely be superseded soon) and the Spanish version has a very long waiting list.
Has anyone figured out how to travel on an airplane in Europe with a 300Wh ebike? I think this is forrbidden, the max is 160Wh. I don’t want to be on the airplane on which a 300Wh battery goes off.
Have you contacted Brompton about it or asked in one of the Facebook Brompton groups? Let us know if you find the answer, I’m also interested in this as I travel frequently with it.
I googled te issue. There is now an official policy by all airlines that limits Li batteries to 160Wh. Batteries >160 Wh are now part of the list of dangerous goods that you can’t take with you at all.
All ebike manufacurers know this. This is not only for people carrying planes, they also can’t ship batteries with cargo planes easily any more – there have been several dangerous battery explosions.
At the moment nobody has an idea how to deal with the issue.
Interesting, well that’s a sad situation. I guess I’ll have to continue traveling by train and car as I’ve been doing lately. I’m fed up with security crap at the airports anyway.
HI – we are at nanoelectricbikes.co.uk. We have been fitting electric conversion systems to Bromptons for over 10 years. You can see on our website that we offer 4Ah batteries which mean you can take them on a plane. They give a range of 8 – 16 miles (12-25km) so perfect for the majority of journeys and as the batteries are only just over 1kg each you can always carry a second if you want to go on a longer trip.
What’s the top speed and how does it compare to the official solution?
Lol, Nano giving their pitch then not following up. Their top speed as quoted in their FAQ section is “13/14 mph”. It is noticeably slower than 15.5mph (I’ve tried it) and not that powerful so poor acceleration. Not very useful in my opinion.
It is great that it uses standard power tool batteries that are a lot cheaper so it’s good if you’re ok cruising at lower speeds.
The Zehus is very smart, but you loose the gears, and having the battery in the hub means it is close to impossible to ever change the battery, The Spanish solution is barely available and the primitive cadence disc is not convincing at all. The Brompton measures cadence and torque, and this works really well. I like the front wheel solution as I still have gears for faster speed. And there is no significant resistance when riding without electric support.
One could criticise that torque is measured on the left pedal – bad for a right-handed cyclist. You need half a round of pedalling before it kicks in at a traffic light. One could also criticise the external battery, but this has an advabtage for charging off the bike. The response is very good and it looks nice.
Maybe the Gocycle is sexier, it looks very smart, but then the Brompton folds properly, without the need of an any tools – a huge plus.
I think Brompton Williams did a great job, and I will post here my experienced after having done some few hundred miles.
Is the cadence disc the only thing that concerns you in the Spanish solution?
There isn’t that much to an ebike, a motor and some control and when it is to go or not. What makes the difference is weight, size and control. If you don’t have cadence it just goes when you move the pedal. With torque you add a whole level of control and feels much better, and the Brompton soution feels really smooth.
What it lacks completely at the moment is software, the analysis of power distribution, fine tuning etc – they say this is to come, but iOS only, not Android. 🙁
The small bike that has all this right is the gocycle, but they lack the fold.
Right, so what you are saying is that out of all these options the official one is the most advanced solution to come out yet.
The native Brompton is certainly more advanced than the add-ons. What it lacks so far is the software that gives you all the information about power distribution and additional control (have a look how gocycle does this). But this has been announced, at least for iOS.
The Brompton hub also has a clutch, this is why it has no extra resistance when it is off. Not sure whteher the others have this.
A simple test shows you how sophisticated they are. If you liift the native Bromton ebike and start to pedal almost nothing happens with the front wheel, because you have no torque on the pedal. This is why it pulls smothly, and the transition to pure muscular power above 25km/h is also very smooth.
Thanks Ulrich, that is very helpful. I’m going to wait a few more months before I make the investment to make sure nothing better comes out.
The nano is popular here
https://www.nanoelectricbikes.co.uk
Thanks, not much info on their site unfortunately.
…and they do not reply when trying to contact them. I did want a kit mainly becouse of the great battery solutions but after contacting them by mail and trough theyr site no reply- yet.
This looks like one of these cheap and simple but working solutions. Manual controls with a pedal cadence sensor (which is required in the EU). To add a torque sensor you need a lot of software.
You say above you have taken your Brompton all over Europe. How do you get the battery onto an airplane? They don’t allow batteries above 160Wh.
I don’t have an electric version yet so I was referring to the traditional one.
Why do you think the electric concepts hub is better than the Brompton solution. It costs nearly the same, has half the battery capacity, you loose the gears which desperately need when the battery is empty, and changing the battery is a majour repair.
Right now I think the best one I’ve seen is this kit from a Spanish company, but they seem to be struggling with availability due to high demand at the moment: https://ecycles.blogspot.com/p/publicidad.html
I did buy the native Brompton. Drives like a charm, all promises I read about the performance are justified but front hub is broken after a few miles (makes clunking noises). Customer support is good though, they respond immediately, and I have 27 out of 30 days left to return it.
Do you have an opinion on the add-e Sportskit kit for Brompton ?
https://www.add-e.at/produkt/add-e-for-brompton-sport-edition/
No I had not heard of that one till now. Have you seen it in action?
Nope. But its very light, Can be removed in seconds, and their Next edition coming soon will be all wireless exctpt pne cable. Only down thing seems to be the wheel roll and i am a bit concerned abour durability on such a small motor.
Interesting, there’s lots of development happening at the moment so I am waiting until a real leader emerges before ordering my own kit. I’ll probably get a new bike at that point as I quite fancy the idea of having one manual bike and the other with the kit.