Brompton Bicycle Folding Bikes

A transport tool based on craft and design

The right mix of imagination and grit will carry you a long way. In the mid-1970s, engineering graduate Andrew Ritchie was working as a landscape gardener when a cycling enthusiast asked him to come up with a better fold-up bike than the ones available back then.

The idea gripped him – so much so that his initial design triggered what has become a major manufacturing success story. Brompton Bicycle, started by Ritchie in 1976, made 69,000 bikes in 2020/21, around 70 per cent of them for export

The company is now Britain’s biggest bike manufacturer in an age when Asian companies dominate the industry. It has recently added to its range with a new family of electric bikes, which are considerably lighter than most rivals and were developed jointly with engineers at Williams, the Formula One racing team.

The story offers an example of Britain’s ability to thrive as a manufacturing base for higher-value, specialist products where craft skills and design combine with technical ingenuity.

Brompton also exhibits a certain quirkiness. “We make our bikes with incredible tolerances and using some special materials, but we have some fun while we’re doing it,” says Will Butler-Adams, Brompton’s chief executive, who joined the company in 2002 from the chemical industry. Ritchie now has little day-to-day involvement with the business although he retains a large stake.

The company organises a series of bike races – open only to Brompton riders – in cities around the world, some of them including challenges in which riders must pick up their bikes and run through a wall of cardboard boxes, for example.

Brompton bikes have a sturdy design that can withstand the challenges of heavy use on urban roads and the rigours of being carted around when not in use, but at the same time they are remarkably straightforward to fold up, carry and stow away.

“We think of ourselves as a group of engineers who make a convenient transport tool for cities,” says Butler-Adams. Brompton is based in London – where it started – and makes its bikes in an airy factory on a trading estate in the western part of the city. “A lot of other places – in the UK and elsewhere – have asked us to set up a factory,” says Butler-Adams. “But we think our brand of ‘Made in London’ is incredibly powerful and helps us in our sales efforts around the world.”

After rapid expansion forced Brompton to consider a second factory in 2022 the company announced plans to open another plant in Ashford, Kent, at a cost of about £75m. The new facility is likely to open in around 2027, with the existing plant operating in tandem until about 2030.

Brompton has had some success with its new electric bike - with a new transmission that brings the weight including the battery to about 17kg, compared to more than 20kg for many competing models. “The lower weight gives us a competitive advantage,” says Butler-Adams.

Butler-Adams describes much of the process of designing and building a Brompton bike as “simple physics” but the company has gone to great lengths to ensure the reliability of the folding mechanism so that – even when a bike has been collapsed and unfolded hundreds of times – it remains safe to ride. “Bikes don’t like being cut up into bits,” he observes.

To cope with these demands, Brompton either manufactures or commissions virtually all the 1,200 components that go into each bike. The way the parts are assembled or joined is controlled using about 500 jigs and fixtures, which the company has devised itself to hold parts in place or guide the way assembly workers use their tools.

Each bike is held together by about 100 joints created by brazing – a technique well suited to light and thin metal parts but one that is hard to master. Brompton employs about 45 brazers, each of whom has completed more than a year of training under Abdul El Saidi, the company’s head of brazing.

Other processes used in the bikes’ construction also involve a lot of time and attention, most of which is invisible to an outsider. The accumulated knowhow is stored in employees’ memories or set out in hundreds of thousands of drawings that the company keeps to itself.

These hidden capabilities explain why Butler-Adams is relaxed about letting competitors look round his factory. “We know that no matter how hard anyone looks they will find it very hard to take our engineering ideas and replicate what we do.”