BrakeFast Schlumpf Brake Adaptor

Some of you geared riders will know about the work that has been going on for the last 2 years on a way to fit an internal disc brake on to a schlumpf hub. The design journey has been catalogued on the Facebook Geared Chat group.

The “Brakefast” project was an open source design project lead by Martin Charrier and myself to design an adaptor to the hub that allows a brake to operate on the rim side of the gearbox and be internal to the frame. The project has had lots of helpers and supports, this is real a community project! Although I will say special thanks to Maksym Siegienczuk who found us the manufacturer.

The Schlumpf hub has always had a problem with the disc fitting on the KH moment/spirit cranks as it transferred the braking action through the gear mechanism so reducing it’s life. It also had additional installation problems.

The “Brakefast” adaptor is for the Schlumpf geared unicycle hub. This adaptor fits on to the left-hand hub flange and gives the Schlumpf hub an internal disc fitting. We have also found a relatively easy way to install a tab on the other side of the frame with the Brakefast tab adaptor

The design process was made interesting with the introduction to the market of the 32 hole carbon rim and finding out that the hubs had 2 different PCD’s. in the UK have agreed to finance a batch of these and are looking for people who would like to pre-order some. The product is on the website here, but we ask people to also express interest in an adaptor on the facebook group or contact me directly.


Looks just like the ones I have been building for several years. Great job getting these out to the Schlumpf riders. These are really good for our geared friends.

                                                                Thanks Mark, (Lobbybopster)

That’s a neat design you ended up with.I saw some of the earlier drawings, I like the changes that were made. (especially that all the versions are 2 piece now)

Is getting the brake disk themselves laser cut an option you have thought about? Even in low quantities, it might be cost efficient vs. throwing most of a Shimano rotor away. I’m not sure how (or if) brake rotors are heat treated or ground after being cut out though, so that may be an issue.

Fascinating! I’ve been following along some of the posts on Facebook. I’d like to throw in some basic questions for the less-technical users:

  1. I replaced my original (2010) KH frame with a later one, with disc brake mount, when I upgraded to a disc a few years ago. That mount is on the right side. I remember spending many hours with a file to get everything to line up. I haven’t had a problem with this setup, but am concerned with the “extra wear & tear” this setup puts on the hub. I’ve already killed one hub. The question: Would I need a new frame, or to customize my current one? If your photo is of one on the left side, this would appear to be a yes.
  2. What’s the weight savings with a carbon rim? I have the Nimbus one with the holes.

Thanks to everyone working on the project; a labor of love for little or no money, for a small group of enthusiasts. :slight_smile:


The brake caliper has to be on the left with this setup. So yes you need to get a new frame - good news is: @MAD4ONE just announced a 36" frame with brake tabs on both sides. Or, cheaper alternative is to get a D-Brake adapter. In this case, it would probably be a good thing to add something to strengthen the D-Brake as the forces going thru it on a large wheel are huge.


Alternatively UDC is also selling a weld on brake tab as well as a bracket to properly position it from a d-brake.
In the grand scheme of things, paying a welder and a powercoating place would seem pretty cheap, and no doubt cheaper than the future Mad4One frame (as nice as that’s going to be).

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D’brake tab is not a problem to use. It now comes with an anti-vibration bar which should allow it to be used on the any size rotor without a problem.


What a nice project and piece of work! :open_mouth:

If I am to build/rebuild a Schlumpf wheel, this Brakefast thingy is definitely going to be part of it.

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I was lucky enough to be able to try out the first prototype of the BrakeFast. I rode nearly 500km in September-October 2020. I would have liked to continue, but with the restrictions due to the health crisis and the winter weather, I’m more willing to go off-road.

I really like this set-up with the 36" carbon rim, and although the braking is improved, what I like the most is to be less unbalanced when there is side wind (there is wind almost all the time in Brittany (region in the west of France))

Here is the photo album with the step-by-step assembly (the final version of the brakefast has since been simplified)

For my part, I am lucky enough to have a great flansberrium frame with brake mounts on both sides. But, for my 2nd schlumpf hub, I opted for the braketab kit (prototype too) and I had a support welded on a KH29 frame. I have other KH frames that I like a lot (the way KH frames fit the bearings is just perfect), so I take the opportunity to update them by having supports welded on each one.