The MTBrompton is, as the name suggests, intended to be a mountain bike version of the Brompton – with space for 20″ tyres up to 2.4″ wide, it still folds like a Brompton but can handle some pretty rough off-road tracks!
- What is it for? I’m not sure! I built it to see if it could be done, I assumed a few people might want to have a folding MTB to play with, but quite a few people have also asked about using it for rough touring. It can take fatter touring tyres too, like the 2.4″ Big Ben tyres from Schwalbe.
- What about racks and mudguards? No, I’m afraid not – not the standard Brompton ones anyway. It should be possible to fit different racks and guards intended for 20″ bikes. My integral rack won’t fit either, the jig isn’t designed for it.
- What are the “ears”? They are for it to stand on when folded. The folded bike rolls nicely on the back wheel (with no mudguard of course), so it doesn’t need rollers there.
- Can I fit wider bars for off road? Definitely – my prototype has standard S-bars, but because it’s higher when folded there’s plenty of room for wider bars without affecting the folding.
- Is it too high? It is quite high, the bottom bracket height is 350mm. That’s in the upper range of what mountain bikes have, but it’s not ridiculously high, and it does help with clearance for the big chain ring.
- How do I get one? Really, it’s just front and back kits, like all my other kits – a rear gearing kit (Alfine, Rohloff, Kindernay or Enviolo) and disc brake kits. Order a rear kit, front and rear disc brakes, add £100*, and that’s everything you need.
(*The MTBrompton frame parts are more expensive to make)
Ready-To-Go Kits: To make it simpler, here’s a couple of the most popular options as a kit – each kit comes with forks, rear triangle, wheels, shifter, brakes etc. All you need to add to complete the build is a donor Brompton.
Rohloff MTBrompton Kit with MT5 hydraulic discs – £2425
Alfine-11 MTBrompton Kit with cable discs – £1435
Complete Bikes: For a complete solution, I can also build the entire bike for you – here’s a couple of complete MTBrompton builds, they come complete and ready to ride. When you order, let me know what handlebar type you want (low, mid or high) and what colour.
Rohloff MTBrompton Complete with MT5 hydraulic discs – £3675
Alfine-11 MTBrompton Complete with cable discs – £2685
