Monster Brompton Challenge part 2: Putting a folding mountain bike to the test

Back in 1975, driven by the congested roads and busy public transport of London, Andrew Ritchie was inspired to create a folding bike. It turned out to be a pivotal moment in the history of cycling with his idea blossoming into the Brompton bike.

Now one of the most iconic bikes in the world, the Brompton was characterised by its three-part folding system that allowed a rider to break the bike down so that it was convenient and easy to carry. It was a revolutionary design that completely transformed what was possible when commuting by bike. Cyclists could easily combine riding with public transport on their commute, while they didn’t need to worry about locking their bike up safely as a Brompton was compact enough to follow them indoors.

It’s a successful recipe that has remained largely unchanged over the years, barring the various colourways and an electric version, but nothing has strayed too far from the original… Until now!

GCN’s Alex Paton recently stumbled across the mysterious world of modified Bromptons. One of the leaders in this murky area of the cycling world is Kinetics, a website that provides everything you need to build a custom Brompton.

Hardcore Brompton fans may consider it sacrilege, but we wanted to find out more, so Alex got his hands on some modified kit to build his own custom mountain bike version of the popular folding bike. His custom machine combined 20-inch wheels, up on the traditional 16-inch, with noticeably knobbly tyres, disc brakes and an 11-speed internal gear hub.

• Read more: Monster Brompton Challenge: turning a Brompton in to a folding mountain bike

With the Franken-Brompton built, it was time to take it our for a test ride, so Alex recruited the help of Si Richardson. Excited but also slightly cautious about the new design, the duo put the bike through its paces across a range of off-road terrains, but how would it stack up?

Find out how they get on in the video at the top of this page.

Discover more of our challenges and adventures on the ‘Lifestyle’ section of the GCN website, linked here.