Brompton Disc Brakes

SONY DSCThe normal brakes on a Brompton are, well, “adequate” – the latest versions are okay, but sometimes more powerful brakes can be a good idea.

I make several brake conversions for the Brompton – fitting disc brakes gives you much more powerful braking, which is also almost completely unaffected by the weather, mud or road dirt. Fitting disc brakes needs fittings welded on to the frame, but the disc brakes can’t be retrofitted to existing forks, they’re too narrow, so as with the Rohloff Brompton kit I make completely new forks in Columbus Zona steel.


Front Disc Brakes: Don’t forget to tell me which colour you want the forks painted. Kit includes a new fork, front wheel, brake caliper, rotor and everything else you need.

Front Spyre Cable Disc Brake, New Forks: £430
Front Magura MT4 Hydraulic Disc Brake, New Forks: £430
Front Magura MT5 Hydraulic Disc Brake, New Forks: £450
Front Hope Race XCR Hydraulic Disc Brake, New Forks: £595  

I can also build up the front wheel with a SON Delux hub and add an Edelux II front light and a rear light if you want to add top quality dynamo lighting at the same time, as shown in the above picture. Or the SP hub dynamo and Avy light is a more affordable option.

Front Spyre Cable Disc Brake, New Forks, SON Edelux lighting: £830
Front Magura MT4 Hydraulic Disc Brake, New Forks, SON Edelux lighting: £830
Front Magura MT5 Hydraulic Disc Brake, New Forks, SON Edelux lighting: £850

Front Hope Race XCR Hydraulic Disc Brake, New Forks, SON Edelux lighting: £995  

Front Spyre Cable Disc Brake, New Forks, SP Avy lighting: £630
Front Magura MT4 Hydraulic Disc Brake, New Forks, SP Avy lighting: £630
Front Magura MT5 Hydraulic Disc Brake, New Forks, SP Avy lighting: £650

Front Hope Race XCR Hydraulic Disc Brake, New Forks, SP Avy lighting: £795  

Rear Disc Brakes: Because the normal Brompton rear frame won’t work with disc brakes, for these kits I’ll assume you’re fitting either my Rohloff Brompton kit or Alfine kit at the same time. So this kit includes only the brake caliper, rotor, and all parts needed to fit with a gearing upgrade kit.

Rear Spyre Cable Disc Brake: £110
Rear Magura MT4 Hydraulic Disc Brake: £110
Rear Magura MT5 Hydraulic Disc Brake: £130
Rear Hope Race X2 Hydraulic Disc Brake: £295 

39 Replies to “Brompton Disc Brakes”

    1. That seems similar to the Nano kit. That motor won’t work with a disc brake, but at least with Nano they can do a different motor which is disc-compatible – best ask V-fiets.

  1. Disc brake forks on large wheel bikes are generally heavier and stiffer than those for rim brakes in order to cope with the increased force concentrated on one side of the fork. How do you manage to make your disc brake Brompton forks so light?

    1. Brompton forks are much smaller than big wheel forks, so the forces are different – it’s not necessary to use special heavy-duty fork blades, though I do use long-tang fork crowns to spread the load.

  2. After a Brompton has the Rohloff kit , front and read disc brakes , plus a gates drive , will the bike fit inside the B&W travel hardcase ?

    1. Yes, it still fits – you need to trim the foam padding a bit, and it’s a bit more of a squeeze, but it does fit in.

  3. what is the width of the forks, is it 100mm? I’m looking to fit a front hub motor compatible with disc brakes, what specifications/dimensions of a motor should I opt for?

  4. I have a 2016 black edition (lime green). Is it possible to get the wheel in black? If possible, are there additional fees involved? Would appreciate further info on it. Thank you.

  5. Do these brakes have to be bleed frequently, as the caliper will be moved from side to side, and then stored upside down for at least a few hours per day, does this mean that they have to bleed frequently.

      1. I’ve had mine for a few months and it actually spends more time “upside down” folded at the office and such but no problems at all. It is a well worth investment for peace of mind if you ride anywhere other than flat roads. Even the newest brompton brakes are adequate at best and still generate too much heat in the descents leading to tube failures sometimes in a violent manner. (Especially if you are like me and weigh a bit more than a “normal” person)

  6. For the front hub, is there any 74mm front hub with Disc mount on it? and do you have the 74mm fork with disc brake support?

  7. I was planning on going for the alfine rear hub with the Hope evo race 2 brakes . Is the front hydraulic a hope unit as well with the same break lever.

    1. Yes – though because of different frame tube treatments, it’s not exactly the same shade of metal that shows through, but pretty close.

  8. I understand the disc brake is normally installed on the left side of the bike, but since you’re customising anyway, maybe the front disk brake could be fitted on the right side of the front wheel instead so that it does not interfere with the Brompton fold.
    Just a thought.

    1. The disc brake on the left doesn’t interfere with the fold, and if it was on the right it’d be on the outside, perhaps more easily damaged when folded.

    1. If you want to have a front hydraulic brake but keep the existing Brompton gears, then you have to fit a different 3-speed shifter – the Sturmey ones are good. Alternatively, the cable disc brakes work with the existing brake lever and shifter.

    1. Theoretically yes, but I don’t offer that at the moment because I’m not set up to make through axle Brompton forks and it would make things like the axle hook more difficult.

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