The Brompton Folding Bicycle

Brompton M3L

[Having owned three now, this article should be read with the presumption that I’m a big fan of Brompton folding bicycles. In other words, consider it more of a general overview of Bromptons written by a devotee, rather than an unbiased, technical road test of a specific model. —ed.]

The Benefits of Folding Bicycles

Folding bicycles offer many advantages to commuters, tourists, and anyone who needs a bike for transportation, but has limited space for storage.

In many cases, bike racks on buses and trains are available only on a first-come, first-served basis. This leaves owners of full-sized bikes vulnerable to being bumped off of transit in the event a rack is full. Folding bikes solve this issue by being allowed inside many buses and trains. When hidden by a slip cover, a tiny folded bike like the Brompton is no bigger than a small suitcase, and even if regulations state otherwise, they can often be brought on-board and stored in a luggage area.

Brompton M3L

Small folding bikes are often exempt from building regulations that bar regular bikes from entering. In addition, they open up a variety of storage possibilities at the workplace, while also eliminating the security issues associated with storing bikes outside. A folded Brompton is small enough to fit under a desk in even a tiny cubicle.

Brompton M3L

Multi-modal touring is an appealing option for those who either have physical limitations or time constraints. With a small folding bike, a person can cover a portion of their tour by train, plane, or bus, then use their folding bike for exploration at various destinations along the way. We’re very interested in the idea of taking a train across the country with our pair of Bromptons, stopping along the way to explore the sights in various locations.

Brompton M3L

If limited storage space at home is an issue, folding bikes are a great way to make the best use of the space that is available. Compact folding bikes like the Brompton are small enough to be stored under a desk or even inside a cupboard. And for those who are sensitive about the visual effect of having a bicycle stored in their living space, a small folder with a slip cover makes an unobtrusive package that disappears into a corner or cubbyhole.

Brompton Company Background

The story of Brompton is the quintessential tale of the inventor/entrepreneur who had a vision, brought it to reality through a long process of experimentation and prototyping, and eventually brought a mature product to market in a very successful way.

Brompton’s owner, designer, and current Technical Director, Andrew Ritchie, first had the idea of developing a better folding bike in 1975 after seeing a Bickerton. From that initial spark, it took 13 years of prototyping and fund raising to reach the point of full production in 1988. The Brompton as we know it has been in continuous production since then. Throughout, the company has remained under private ownership, and production has remained in-house in West London, UK.

Today, Brompton has a cult following unlike practically any other bike brand — folding or otherwise. Brompton clubs exist all over the world, and numerous online communities have sprouted up around the brand. The so-called “Brompton World Championship” — a somewhat tongue-in-cheek annual race with entrants dressing in business attire and riding Bromptons — has become wildly popular, with 750 participants this year.

The Brompton Fold

Any discussion about a Brompton starts and stops with the fold, which is arguably the best among all folding bikes. The parallel, three-part fold places the wheels side-by-side, with all of the vulnerable parts protected between the wheels. The overall folded dimensions are 22.2” x 21.5” x 10.6”. That’s a small package for any folder, particularly for one that rides so well. But, even more important is the clean outline of the folded package. The size and shape are not unlike a small suitcase, with the nose of the saddle cleverly serving as a carry handle. With a slip cover over the top, the folded Brompton is so compact and smooth that it can be carried into almost any venue without raising an eyebrow — most people won’t even realize it’s a bike.

The Brompton fold is a three-step process, as follows:

  1. Start by flipping the quick release located under the seat clamp and lifting the back of the bike to swing the rear wheel forward under the frame. Cleverly, in this position the bike is designed to stand on its own. Brompton owners often use this partially folded position to “park” their bikes.
  2. Next, release the hinge on the main frame and swing the frame back on itself, locking it into position.
  3. Finally, release the hinge at the base of the stem/riser, fold the bars, and lower the saddle. The bars snap into place, and the seatpost locks the entire package for carrying.

The entire process takes 10-20 seconds and becomes second nature in a very short time.

Brompton M3L

Cleverly, the Brompton has a pair of tiny wheels strategically placed at the top of the rear triangle for turning the bike into a rolling cart. When the rear triangle is folded underneath, the small wheels swing around to face the ground. With the handlebars unfolded, the bike can be rolled along on these wheels, much like an airline luggage cart.

The Ride

Bromptons are unusually quick and compact, though not at all unstable or uncomfortable. The 16” (349mm) wheels and compact frame make for a light and nimble feel. The steering is razor sharp, with small inputs at the handlebars being immediately transmitted to the road. It takes a brief time to adapt to the quick handling, but once the rider is acclimated, the Brompton becomes a formidable tool for zipping and weaving through dense, urban traffic.

Brompton M3L

Small wheels tend to provide a harsh ride. Brompton mitigates for this with a suspension block located where the main frame and rear triangle meet. The travel at the rear wheel is short and, unlike the long travel suspension on mountain bikes, is only intended to take the edge off of small obstacles. This small amount of rear wheel travel does a remarkable job of smoothing out imperfections in the road while helping the bike track straight over rough surfaces. The use of relatively high flotation tires run at reasonable pressures (I run Schwalbe Marathons on my M3L at 60psi) also does much to smooth out what might otherwise be a fairly harsh ride.

Brompton M3L
Brompton M3L
Brompton M3L

Bromptons are only available in one size and three handlebar styles, none of which can be adjusted for height. This results in a bike that will feel and fit differently depending upon a person’s physical stature. A Brompton will feel much like a “full-sized” bike to a small person who is accustomed to riding small frames. On the other hand, a Brompton may feel on the small side to a larger person (say, over 6’0”) who is accustomed to riding large frames. This is not necessarily an issue, and many people of all statures, including those well over 6’ tall, adapt to riding Bromptons successfully.

Folding bikes in general have a reputation for being only good for short rides in the city, but Bromptons have been widely used for long-distance touring. In fact, there are a number of people who have taken transcontinental trips on Bromptons, and I know of at least one couple who made a ‘round-the-world trip combining boat and train travel with their Bromptons. Just recently, Todd Fahrner, owner of Clever Cycles in Portland, took an unsupported tour down the California coast (from Portland to San Francisco) on his Brompton.

The Build

Bromptons are built like tanks. That doesn’t mean they’re unusually heavy; they’re not. But where it matters — namely the frame and hinges — they’re clearly designed to withstand many years of hard use. The main frame is built from brazed (not welded), high tensile steel. The over-sized main tube is stiff, and there’s no sign of flex that comes from either the frame or the hinges. The handlebar stem/riser — a weak area among many folders — is surprisingly stiff. The frame is on the verge of being overbuilt, but folders other than Bromptons are notorious for coming apart after a few years, so I feel the robust design is a fair trade for a small amount of added weight.

Brompton M3L
Brompton M3L
Brompton M3L

My M3L’s Sturmey Archer 3-speed internal gear hub performs quite well and compares favorably to modern hubs from Shimano and SRAM. Shifts are crisp and can be initiated while pedaling, coasting, or standing still. I really like the Brompton proprietary thumb shifter too; it’s easy to use and it stays in adjustment. The 3-speed is arguably the best among S-A’s offerings. The 5-speed S-A on my Pashley was clunky in comparison; it needed frequent adjustment and missed shifts were not uncommon. I’ve had zero issues with the 3-speed.

Brompton M3L
Brompton M3L

The Brompton M- and S-Type cockpits are not particularly ergonomically-friendly. As necessitated by the compact fold, the brake levers are on the short side, and the grips are thin and narrow. Ergons are a big improvement over the stock grips; if you go this route, be sure to check that they don’t interfere with the fold.

I find the new Brompton saddle to be more comfortable than previous incarnations. It also has a hand grip on the underside of the horn for carrying the bike when folded; clever!

I’ve owned three Bromptons and I’ve yet to have any issues with components or wheel builds. The Brompton-branded dual-pivot brakes are snappy and and plenty powerful. The Brompton-branded crank is attractive and plenty stiff. The chain tensioner keeps the chain taut when the bike is folded. The wheels are tough and require only occasional touch-up. The overall component mix is excellent, and the detailing, fit, and finish leave very little room for improvement (other than perhaps the hand grips mentioned above).

Brompton M3L
Brompton M3L
Brompton M3L

You may have noticed that each Brompton model number consists of two letters and a number. The first letter indicates handlebar style (S, M, P), the number indicates the number of gears (1,2,3,6), and the second letter indicates fender and rack packages (E, L, R). So in the case of our M3L test bike, we have a mid-rise handlebar (M), 3-speed drivetrain (3), and fenders (L).

Brompton M3L

Each Brompton is essentially “made-to-order”, with a wide variety of options available. There are three base models, the S-Type, M-Type, and P-Type. The S-Type is the sporty model with a lower flat bar; the M-Type (as shown here) is the classic Brompton with a mid-rise bar; and, the P-Type is the touring model with a trekking bar that provides multiple hand positions. Any of these models can be upgraded to the “super-light” package (indicated by an “X” after the model number) with a titanium fork, rear triangle, fender stays and pedal bolt; and, an alloy headset and seat post.

All three models are available with either 1, 2, 3, or 6 speed drivetrains. The 1-speed is a standard single speed freewheel; the 2-speed is a proprietary Brompton-made 2-speed derailleur; the 3-speed is a variation on the classic Sturmey Archer 3-speed internal gear hub; and, the 6-speed is the 2-speed derailleur in combination with a wider range 3-speed Sturmey Archer IGH.

Brompton M3L

Fender and rack options include the Version E, Version L, and Version R. The Version E is the basic model sans fenders and rack; the Version L includes front and rear fenders; and the Version R includes the fenders plus a rear rack.

Various other options include: extended and telescoping seatposts for individuals with >33” inseams; choice of tires; choice of saddle (stock or Brooks B-17); battery or dynamo lighting systems; and, a variety of luggage options, which I’ll cover below.


The Brompton Front Carrier Block is a universal mount that accepts any bag in the Brompton line-up. The block is attached to the headtube, which places the weight on the frame, leaving the steering essentially unaffected.

Brompton M3L
Brompton M3L

NYCeWheels sent us a full range of Brompton bags to try out, from the simple Folding Basket, all the way up to the A Bag leather briefcase:

  • The Folding Basket is a grocery-style pannier adapted to fit the FCB.
  • The S-Bag is a small messenger-style bag with a 20-liter capacity designed to fit the lower handlebars and shorter stem on the S-Type bike (it also fits the other models). It’s constructed from water-resistant nylon and comes supplied with a waterproof rain cover and shoulder strap. This is a nice bag if you only carry a lunch and a few small items to work.
  • The C-Bag is a full-sized messenger bag with a 25-liter capacity. It’s constructed from water-resistant nylon and comes supplied with a waterproof rain cover and shoulder strap. The C-Bag is a nice size for commuting, with enough room for a change of clothes, lunch, and even a small laptop. With the addition of a little padding, it also serves as a nice camera bag for a small DSLR outfit. This is my favorite bag from Brompton.
  • The T-Bag is Brompton’s touring model. It’s their largest bag with a 31-liter capacity. It has a roll top and numerous pockets and pouches inside and out. It comes supplied with a rain cover. This is a big bag that’s perfect for touring or grocery hauling, but perhaps a little large for commuting.
  • The A-Bag is Brompton’s leather executive briefcase. It’s a beautiful piece of work, but it’s a bit ostentatious (and pricey) for this humble commuter.
  • The B-Bag is a carrying bag for the bike itself. It’s a heavy duty bag with casters, a carry handle, a shoulder strap, and 5mm padding all around. With the use of a pair of B-Bags, we’re able to drop both of our Bromptons in the cargo area of our tiny car without fear of damaging the bikes. A must-have if you plan to transport your Brompton in an automobile or airplane.
  • The Slip Cover is a small cover that slips over the bike from the top. It makes it much easier to sneak the Bromptom into buildings and onto buses and trains without notice. It stores on the seat post when not in use.
Brompton M3L

When I think of a Brompton bicycle, I think “clever and refined”. From its unique fold, to its suspended rear triangle and “rolling cart” capabilities, this is a bike that’s oozing with intelligent details. The underlying design of the Brompton has changed very little over the years; the bugs and quirks have been almost completely worked out of this bike through a long process of testing and refinement. While there are other interesting folding bikes on the market that offer viable alternatives to the Brompton, in my view there’s yet to be another folder that brings together a clean, compact fold and excellent ride quality in such a compelling way.

M3L Specifications
  • Frame & Fork: Steel
  • Handlebars: M-Type
  • Saddle: Brompton with moulded grip and hollow rails
  • Seatpost: Brompton steel telescopic
  • Pedals: Brompton folding/platform
  • Brakes: Brompton dual-pivot caliper
  • Shifter: Brompton
  • Front Hub: Brompton standard
  • Rear Hub: Sturmey Archer BSR 3-speed internal gear hub
  • Rims: Alloy
  • Tires: Schwalbe Marathon
  • Folded dimensions: 22.2” x 21.5” x 10.6”
  • Weight as shown: 25 lbs.
  • Approximate price as shown: $1,424

The M3L discussed in this article was supplied by our sponsor, NYCeWheels. For more information about our reviews, read our review policy.


41 Responses to “The Brompton Folding Bicycle”

  • Judd says:

    Would it be possible to add a Wald folding basket to the rear rack? I have had good luck with them on full sized bikes and really like how they are out of the way the 95% of the time that they are not needed.
    Great review, I did not think I needed another bike (my wife sure dosn’t) but now I am not so sure. It would be the unstopable commuter, bike to bus to taxi to train to… ect.

  • Alan says:

    Hi Judd,

    I’m pretty sure a folding basket on the rear rack would interfere with the fold. A better choice would be the Brompton folding grocery pannier on the front carrier block, which would serve essentially the same purpose.


  • Jesse says:

    Hey there Alan, spoken like a true Devotee! Kidding, that came off sounding fair and balanced to me. One question though, do you know what the weight limit is? Talking about rider size here, not so much worried about cargo ;-)
    I’m a big guy and have noticed that most folders have a limit either right at or just under my current weight…

  • Alan says:

    Hi Jesse,

    Oh, I’m definitely biased… :-)

    The weight limits are 242 lbs. for the rider, plus 44 lbs. cargo. This is on the upper end of weight limits for folders, with most being around 225.


  • Jesse says:

    Drat! As I suspected…back to the diet, I’ve got a ways to go.


  • voyage says:

    The Brompton is too good and too expensive to safely use to conquer the vexing first mile (or two)/last mile (or two) problem of American mass transit: sadly and essentially, you would be asking to be stalked and mugged.



  • Brian C says:

    I have ridden one in our hilly locale, and was impressed at how easily I conquered the hills with the 6 speed (a greater range than on my wife’s 8 speed shimano alfine). And I can definitely see the advantages of this bike for travel (I guess I am not paranoid enough to consider that having a nice folding bike would make one a target). And I love the colours Alan picked for his (must admit I enjoyed playing on the nycewheels site with the colour combinations that are available).

    Now just have to do enough travelling to justify the expense of another bike (grin)…

  • Chris says:


    I have a Brompton, and I live in a rough part of Manhattan. Doubt I’d get mugged for the Brompton – people don’t mug for things that aren’t easily fence-able and I don’t think the Brompton fits that category – deliverymen aren’t going to be buying stolen (impractical), stripping for parts is impractical as well (wheels, tires, hubs, etc are all custom sizes and parts) and besides I think you’d be riding your first/last mile on the bike so you’d be less likely to get mugged as well. The usual city-living caveats for looking out for suspcious perps applies no matter what. I would also hope that most Brompton owners are respectable enough to not buy stolen bicycles. Also given how rare Bromptons come up on Craigslist and the like, it seems a Brompton is hardly a worthy target.

    P.S. Alan – these pictures are gorgeous!

  • Alan says:


    I think it depends upon where you live.

    Also, I have to wonder if bike thieves, muggers, etc., would recognize the specific value of a Brompton compared to less expensive folders. From what I hear, most thieves are on the lookout for carbon racing bikes.

  • Jay says:

    …”sadly and essentially, you would be asking to be stalked and mugged.”

    Any more than you would be just by, say, wearing nice clothes while using public transportation? Or using an ipod? Or some other fancy phone? Any of those things might be indicators of wealth or a full wallet, as far as a thief is concerned.

  • antbikemike says:

    I love this bike! People always ask me about building some bikes like the ones I made for Betsy and I
    …I tell them to buy a Brompton! Someday I wil replace our ANT folders with Bromptons

  • Pete says:

    I like folders, and the Bromptons certainly have their devotees. There is just something about the Brompton “cult” that bothers me, in a way the Bike Friday and Rivendell “cults” don’t, but I can’t put my finger on it.
    Anyway Alan, your Brompton review is great with beautiful photos as always. I’m sure it will sell as many bikes as your Sam Hillborne review did!

  • Molnar says:

    Brompton versus Bike Friday tikit. Any thoughts?

  • Alan says:


    I’m supposed to get a Tikit on loan here pretty quick, so I’ll have more thoughts then. Here’s my take right now…

    The BF Tikit has a quicker, but less compact fold.

    The Tikit is available in multiple sizes, so it’s easier to get a fit that more closely approximates the fit on your “regular” bike, if that’s important to you.

    The Tikit has an adjustable riser, but that adjustability comes at the price of more flex in the front end.

    It seems Bike Fridays speak to some people, while Bromptons speak to others. You’ll have to figure out which cult you belong to… ;-)


    PS – They’re both sweet bikes, and I can’t imagine anyone regretting purchasing either.

  • Alan says:


    “I love this bike! People always ask me about building some bikes like the ones I made for Betsy and I …I tell them to buy a Brompton! Someday I wil replace our ANT folders with Bromptons”

    That’s quite an endorsement, Mike!


  • Lovely Bicycle! says:

    This has got to be one of the most complete bicycle reviews I have ever read, thank you for the rich and well organised information. This will be my go-to Brompton reference page for sure!

  • kanishka says:

    great demo of features. thorough. awesome to see a folder highlighted in one of my favorite sites.

    i think brompton should rethink its original statement about only considering using 3 speed IGH’s, because of inherent inefficiencies of anything beyond 3 gears. i think the current 7/8/9 speed IGH’s are ready for brompton prime time.

  • Alan says:

    @Lovely Bicycle! – Thank you!

    @Kanishka – I’d love to see an 8-speed IGH on the Brompton. One of the issues is the narrow dropout spacing, which is required to keep the folded size to a minimum. Sturmey Archer makes this hub specially for Brompton. As it is, the Shimano and SRAM hubs won’t fit, though I have seen some elaborate retrofits.

  • Urb Anwriter says:

    Oooooooh. Here’s the question; how, exactly, do I justify riding my Loring ‘most of the way’ to work, while carrying the Brompton, and then make a ‘modal shift’ on to the Brompton, when my every-day commute to work is .6 km? Oooooh, do I care how I justify it?

    Slightly off topic, I think, but did Mike and Betsy get the bike(s) that were stolen, back? Hope so.

  • todd says:

    @kanishka, note that the current brompton 6-speed offering has the same range as a nexus 8, at about half the weight. diminishing returns here…

  • voyage says:

    @Chris, @ Alan,

    It depends on many things.

    One would think Brompton, like any company, wants to sell many, many more Bromptons. If they succeed in expanding their units sold and develop a mass following, it would seem the risk of owning a Brompton increases: thieves tend to follow the market. It’s something to consider when evaluating TCO.

    Honda, Toyota, Nissan automobiles (and variants: Lexus, Infiniti, etc.) are the most stolen automobiles for over past twenty years and it’s a stable, robust finding, nationwide.

    What should Brompton do?

    Only sell their bikes in certain safe areas?

    Avoid carbon?

  • Malcolm says:

    I’ve owned my Brompton M3 for three years now and have ridden it mostly in Manhattan but also in the hills of Western Massachusetts. It always gets a lot of attention even though there are a lot of them in NY now. i’m often demonstrating the fold to pedestrians on the Upper West Side (hopefully not future muggers!) It really is my go-to bike and sits neatly by the back door of my apartment thus avoiding the bike room snarl. All this and apparently free membership in a cult!

  • Tom says:

    Brompton versus 20″ Brompton with IGH, like the Mu XL Sport or similar. Any thoughts?

  • Tom says:

    Brompton versus 20″ Dahon with IGH, like the Mu XL Sport or similar. Any thoughts?

  • velojoy says:

    I’ve been considering a folder as an antidote to the bike clutter accumulating in the dining room of my NYC apartment. Your review inspires me to test ride a Brompton sooner rather than later. Thanks, as usual, for your thoroughness and great photos!

  • kanishka says:


    the fold is easier, faster usually

    brompton has something called the standing position, which is incredibly useful.

    dahon accomodates klickfix into their frames, so you have a wider selection of klickfix compatible front bags, but brompton bags are designed to much more fluidly move and be used with the bike

  • Karl McCracken (twitter: @KarlOnSea) says:

    I’ve just bought a second hand Brompton – a useful option if you find the price tag a little too eye-watering.

    If you go down this route, you can typically save ~30% on the new price (they hold their value well, due mainly to the build & component quality). But there are also things to look out for – this Ebay buyers’ guide for Bromptons includes the things to look out for.

  • Jim says:

    Awesome photos, as always. Also, as far as luggage goes, I believe the
    Zimbale brand saddlebags work well with the Bromptons and don’t interfere even when folded.

  • The Touring Bicycle | Bike Touring News says:

    […] at Ecovelo also posted this article about the Brompton folding bikes. These bikes fold into a very small package making them easy to […]

  • Patrick says:

    There are several after-market tinkerers which can modify the rear end to take a shimano nexus or an Rohlof IGH. Kinetics in the UK is an example.

    Here in the Netherlands a 3-speed will do, but I know a few brompton-fans in Germany which made the switch to 8 gears and are pretty happy with it.

    I always liked the Brompton and owned one a few years ago, negative points were the quality of the handgrips, brakelevers and stopping power of the brakes. Also paint quality was quite bad, black seems to be better or take the fabulous looking Raw Lacquer.

  • NYCePeter says:

    You’ve really captured the incredible design Brompton in a such great way. Seeing these pictures takes me back to when I first got my Brompton folding bike and how I spent hours looking over every square inch, taking in all the details, the beauty. Thanks for the excellent review!

  • David O'Sullivan says:

    I read your earlier reveiw of the flat bar brompton, specifically your comments regarding the narrow grips and handlebars. I couldn’t help but notice that the problem seems to be in the brake levers rather than the bars. Switching from the standard brakes to a cross style brake lever each as cane creek cross tops would save 15 – 20 mm on each side, allowing wider grips and a more ergonomic position.

    I wonder if that would benefit this bike too?

  • Al says:

    I really enjoyed that absolutely well written article about the Brompton. The pics too are works of art. I’ve linked this article to my blog :)

    Viva la foldies!

  • Alan says:


    Thanks for the kind words and the link!

    I’m not sure how I missed you; I added your site to my blogroll and RSS feed.


  • jean says:

    The article refers to “tiny wheels strategically placed at the top of the rear triangle for turning the bike into a rolling cart”.

    These tiny wheels can be replaced by the Brompton easy wheels ( equipped with ball bearing. They make a huge difference, especially when the bike comes with a rear rack (4 easy wheels). Pushing a folded brompton becomes easy and efficient, even on “large” distances (train stations, comercial centres…).

  • Chris says:

    We love our Bromptons!

    Cured us of looking at other bikes. Weird.

  • New Bike says:

    […] My nerdiest purchase thus far is a Brompton folding bike. This guy over at Ecovelo has all kinds of positive things to say about the Bromptons, but I think the final nudge came from the folks at Trophy. Hell, even […]

  • Chandra says:

    This is a great post. I believe this post could be useful to someone considering a Brompton.
    Great photos, as usual!
    Peace :)

  • fumble says:

    Great review! Much appreciated!

    This is a little off topic, but can anyone tell me what kind of bikes are pictured with the Bromptons in the fourth picture from the top? They’re beautiful!

  • EcoVelo » Blog Archive » Some Thoughts on Internal Gear Hubs says:

    […] city bicyclist is the ability to shift while at a stop. Regardless of whether I’m riding my Brompton with its Sturmey Archer 3-speed IGH, or my Civia Bryant with its Shimano Alfine 8-speed IGH, I always appreciate the fact that I can […]

  • EcoVelo » Blog Archive » Soma Mini-Velo says:

    […] been riding our loaner over the past few months. Her regular rides are a Rivendell Betty Foy and a Brompton M3L, so I was interested to get her impressions of this unusual bike that sort of splits the difference […]

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