Brompton M6L Electric review

The Brompton M6L Electric is a premium folding e-bike

Brompton M6L Electric
(Image: © Rob Clymo)

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.

Pros

  • +

    Ingenious folding design

  • +

    Built using quality components

  • +

    Deceptively zesty performance

Cons

  • -

    Premium but expensive

  • -

    Folding it up takes practice

  • -

    Not the heaviest but still weighty

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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.

Brompton M6L Electric

(Image credit: Brompton)

Price and release date

The Brompton Electric was first launched in 2017. Prices start at £2,725 (about $3,700  / AU$5,000), and the bike tested here retails at £2,850 (about $3,800 / AU$5,200).

Design

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.

Brompton M6L Electric

(Image credit: Brompton)

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.

Brompton M6L Electric

(Image credit: Brompton)

Performance

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.

Brompton M6L Electric

(Image credit: Brompton)

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.

Brompton M6L Electric

(Image credit: Brompton)

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.

Space is tight
With its clever folding capability the Brompton can be easily stored at home, at work and on the train too.

You’re tired of doing all the work
Battery assistance makes a big difference to easing the pain on a commuter ride.

Don't buy it if

You don’t want to carry your bike
The Brompton folds up, but you’ll have to lug it around from time to time and that’s not going to be for everyone.

The budget is tight
A Brompton bike might be a great practical solution but their handmade build makes them expensive for casual users.

You need a bike for all occasions
The Brompton’s folding appeal is great, but if you don’t need a collapsible two-wheeler there are multiple premium options for similar money.

Rob Clymo

Rob Clymo has been a tech journalist for more years than he can actually remember, having started out in the wacky world of print magazines before discovering the power of the internet. Since he's been all-digital he has run the Innovation channel during a few years at Microsoft as well as turning out regular news, reviews, features and other content for the likes of TechRadar, TechRadar Pro, Tom's Guide, Fit&Well, Gizmodo, Shortlist, Automotive Interiors World, Automotive Testing Technology International, Future of Transportation and Electric & Hybrid Vehicle Technology International. In the rare moments he's not working he's usually out and about on one of numerous e-bikes in his collection.