⚙ Schlumpf hubs produced again

There have been few threads with discussion of this, finding them is the problem… however I got this which probably summarises things:

I’m sure there is more extended discussion in other threads, just can’t remember which ones :slight_smile:

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Broken ropes spokes 6 times, that’s why I was looking for a 125mm witn no disc and 32h

I was intending to get the Oracle 36” frame with 125mm bearing centres to use with the New 125mm schlumpf hub.
I might be misunderstanding the previous posts, but it sounds like there may be a problem with that regards the side of the brake tab? Oracle frames have brake tab on left side, I understand.

Could someone confirm which side the disc brake is on for the new up-coming Schlumpf hubs?
If the hubs are called Kris holm schlumf hubs does that mean the disc is on the right side?


Kris is going to add disc tab on the left side as well with 100mm bearing distance

It is on the left side. A dbrake mount could be used on the right side or the left side on whichever frame

Thanks Bouin and Vogelfrei80,

I heard yesterday these left-tab KH frames won’t be around before a long time. So if anyone wants their uni built on February/March, they should probably use another frame.


In my understanding this is exactly the setup you would want – it will give you the strongest wheel and have the brake attached directly to the hub, and hence braking torque is applied directly to the wheel. If you use something like VCX cranks, the pedal spacing will be the same as a 100mm hub with Spirit cranks, so there is no disadvantage there over a 100mm hub with an external brake.

Using an external disc brake on a geared hub which has a brake mount is, in my option, just a bad idea as all the braking torque has to be transmitted through the gearing – for a 36" wheel in high gear this is not a ‘good thing’.


100% agreed! That’s why the BrakeFast has been designed in the first place. Using an EDB has 2 main disadvantages:

  1. As all the braking torque is applied through the gearing, it tends to wear the hub out faster than normal;
  2. When in high gear, the braking torque is divided by 1.5… And that’s nasty.

This is the exact same plan I have here for my G36er and it’s confirmed to be working as the purchase and build is being done by UDC UK and Roger - who is the designer of the Oracle frame.

It was also recommended to me that only the 125mm hubs are suitable for a 36er wheel build due to the spoke angles on the dished wheel builds for these new 2022/23 hubs.

So a 100mm hub to my mind is for 29ers and below size wise.

As to your previous point re two or one 36er. I’d highly recommend keeping a normal fixed gear 36er around. The weight alone of a geared one makes a difference in terms of the decision to take it out - and I feel very strange riding my G26er in 1:1 - almost like I’m wearing it out for no valid reason. Not that I think it’ll wear out that quickly given my light usage… but any G-wheel is going to be a specific ride/purpose. And I don’t see them really replacing having a fixed wheel of the same size.


From old forum posts, it seems like the original excitement was “wow, now I can have a versatile 24 which can go as fast as a 36”, but times have changed, and the current favorite seems to be a G36 and “wow, now I can go REALLY fast”.

But I retain the old view - surely a 1.5454… high gear on a 24 is MORE than enough, and is nice and portable.

So here is what I ordered (in a moment of incautious madness):

100mm width (because that’s what all the smaller wheel frames need);
32 holes (because easier to get a wheel rim);
disk brake (for long downhills) size 180mm (because that is standard).

I think I will get high-Q cranks (e.g. spirit 127/150) because I want to avoid accidental gear changing.

I have a frame I can use, but it has a D’Brake adapter instead of a welded attachment point.
I’m wondering if anyone has an opinion on whether the D’Brake in some way adds more stress or compromises the Schlumpf hub bearing attachment or needs to be bolted with more torque which might not be good?

Mostly because a 24" with Schlumpf doesn’t ride as nicely as a 36" (much more sensitive to bumps). Being nice and portable is an advantage, but it’s rare that a 29" is significantly less practical than a 24". Do your own testing, maybe 24" is indeed right for you, but I think the tendency to build bigger wheels with Schlumpf hub is as much about stability and bringing the cadence down as it is about speed. To go a reasonable 20 km/h on a 36" you still need to pedal at a much higher cadence than you would ever do on a bicycle.

As long as it’s installed properly (the D-brake adapter getting fully tightened to the frame on one side, so that the torque runs through there and not the bearing), I don’t see an issue for the hub.


thanks for that, maybe I will use the D’Brake.
and perhaps a G27.5 is the “goldilocks size”?

You can add spacer washer(s) in order to tighten the D’brake without adding stress on the bearing.


That said: there are a few frames out there that do need a spacer on the right sid, shown in your picture. Otherwise, the d’Brake will not sit flush on the frame but have an angeled gap to it. The pre-RGB QX-Frames are an example for this. In general: all frames that have a wider gap between bearing cap and frame than the Nimbus and KH.

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thanks all, it looks like some very careful washer selection and filing is in order when “Schlumpf day” arrives. I could even imagine putting some temporary thin squashable strip over the bearing and tightening, then undoing it to see if there is enough pressure on the bearing (or maybe just guess by how freely it spins after tightening with the washers?)

So, update on that point: left-tab KH frames arrived this week. The shopkeeper who told me they wouldn’t arrive before a long time was wrong :grin:
BTW, they are blue again. Thanks @bouin-bouin for the info!


I missed the blue and this looks so good!