KH / Schlumpf Geared 24" mountain unicycling

Thank you for the advice tholub…But it is not really the answer I wanted to receive…

My question is:

Will I be limited in strength if I change the hub of a 29er KH by the geared one?
Or will it be fine knowing that on a huge drops the 29er rim will broke before the geared hub (even with enough tension in the spokes)?

It could also be a security as it is definitely more suitable to broke a 29" wheel than a hub @ 950euros;)

I think you’re asking if a well-built 29" wheel from a KH29 would be weak enough to fail on a smaller drop than would break a geared hub in a unicycle with an infinitely strong wheel… As in, if I do a gigantic drop on my 29er, will the wheel break before the hub, and, as it deforms due to its breakage, cushion the hub and prevent the hub from breaking as well?

I believe that the answer is no; I think it is definitely possible to build a wheel strong enough that you’d be able to use it to break your hub during a drop. That said, just be nice to it, and you shouldn’t break your hub. Kris Holm tested the hub for two years doing drops of up to 2 meters (6.2ish feet!) without breaking it. Now, Kris has really good technique, so a sloppy 1-meter jump to flat ground might be as hard on the hub as one of Kris Holm’s 2-meter drops to a slanted roll-out, so you’d have to keep that in mind as you decide how much punishment to give it, but I’d say if you kept the drops sane and tried to do good rollouts (i.e. not dropping to a flat, static “THUD”), you wouldn’t break your hub in a 29er. After all, it’s designed for that kind of stuff!

I think the hub is rated up to 1.5 meter drops, but I’m assuming that that figure is for people who know what they’re doing when they drop. When I drop, I can’t or don’t control my landings, and, I break things, pure and simple, If I ever put my hub in a mountain uni, I’ll definitely keep the drops under a meter. But who does drops that big on a 29er anyway? I’m sure some of us do, but a 29er is much more of a cross-country unicycle; big drops aren’t as common. So… if you got a hub and put it in a KH29, and proceeded to use the hell out of it, while keeping in mind that large, sloppy drops might not be good for it, I think you’d be just fine.

Hehe. I think that Boulou has been inspired by one of our local South African riders, who busted the rim on his K1 26inch trackmonster on the (first ever) South African Municycling Weekend last weekend. this guy was taking his 29er off some insane drops (1.5metres?). Well, maybe not insane by many other unicyclists standareds, but the biggest stuff we’ve seen locally.

The smaller wheel does feel a little more shaky. I’m going to drop a speedo on it soon so I can compare my sspeeds to what I do on an ungeared coker.

Corbin (in Honduras with limited access)

Well, there may be something to that - you are lower down on a geared 24" than a coker, for one thing, so it is going to take you less time to hit the floor, period. Also I think the play in the gearing is inherently going to reduce your balance slightly - the question tho is how much, and I think the answer is “not much”, as the geared 29 was fine.

However, the 24" I had used a Sun Rhyno Lite rim, and a Schwalbe Table Top SL tyre - I can’t confirm these figures, but manufacturer’s quoted weights are 425g for the former (i.e. quite a light rim), and 560g for the latter (an insanely, stupidly light tyre) - and I certainly can confirm it didn’t weigh much (!). As such, it was responsive and manoeuverable as hell, but equally unstable - not much momentum to preserve it’s speed over bumps, and whenever anything did happen to throw you off (including simple lapses of concentration), it did so very quickly indeed and largely without warning. Hence I didn’t really dare push my maximum speed too much…i.e. not beyond what I could run out of!

(ISTR one longish ride, 44 miles, in which I had half a dozen UPDs - never serious, I ran out of all of them, but on similar-length rides on an ungeared 29er or on the 26 guni, I’d hope to not have any UPDs, really!)

I’d not be surprised if a proper 24" muni, big fat heavy tyre etc., rode better than this on-road, TBH; I was trying it more as an experiment aiming for portability and ease of carrying.


KH26 Guni anyone?

The more I think about it the more I seem to lean towards a KH26" Guni setup. So I will have to make some brake mount adapters and think about handle options. Is there anybody around with this setup? Would be great to hear some more opinions or see some more pictures before I go for it.

If you weren’t set on a KH, Nimbus now do a 26" frame with brake mounts in the right place. Maybe you have considered this already.


I dunno if the schlumpf would work in that frame though - I dunno if it’d be possible with the bearing holders - they’d need grinding out with the special grindy tool as a minimum. I’m not sure if the hub is warrantied in that frame either.


oh yes of course, worth investigating still I think as the frame now has machined bearing housings so possibly similar to the KH, maybe.

Thanks lowlight, I did look at it, but I think my KH29 frame would be better due to its lighter weight, friendlier crown and definitely schlumpfable bearing holders. So I’ll try and make some adapters for the maguras.

I still have to decide on a good rim now:

There’s the Nimbus
and then there’s the Sun Double Wide, the Halo Combat and the Alex DX32. Probably there are other options that I haven’t even found yet.

It should have good braking surfaces and I think I would want to run tires from 2,3" to 3" width. So I wonder, would the Nimbus be good for that, or should I rather get something else?

By the way, sorry for the threadjack, but it seems to fit in here more or less.

26" rims

If you want to use a break stay away from the Sun Doublewide. The DX32 is a bit skinny for a 3" tire (in my opinion) but is still a good rim. I use an Echo rear trials rim. I really like it.

There is also the Try-All rim which is really wide and light but is reportedly very weak (and expensive) but comes in nice colours. (sounds like KOXX doesn’t it)

I just looked at various Echo and TryAll rims. The Echo looks great but at 870g it is quite heavy. Probably hard to get over here too. TryAll have some interesting ones that seem to meet my criteria, so I think I would like to get a silver one of those. How weak exactly are they? I think I will avoid huge drops on this build anyways, for the sake of the Schlumpf… So maybe it would be strong enough for me. I wouldn’t consider myself a very aggressive rider anyways.

Ok Corbin,
Thanks a lot. I was just about to put my money down on a 36er frame to move my hub into and now you’ve got me thinking I should put it in a 24 instead.

As one of the few that have ridden a 24 and 36 guni, if you could only own one geared hub, what would you put it in?

I’ve had fun with my 29guni because its good for road and trail, but am changing because its not GREAT for road OR trail.


Hi Munirocks

I have be ridding a KH26 guni with 135/165mm for more then half a year now.
The handle bar is an old 20" unicycle frame put on the KH rail adaptor.

Before that i ride the KH29 a lot.
I really like this 26" guni for muni/crosscountry style of ridding.
The netherlands is not that hilly so it think this is the best choice for this kind of terrain.

The best part of the 26" is tire choice.
I have 3 different 26" tires for this guni.
26x2.4 schwalbe racing ralf i used this tire in the summer with 135mm.
26x3 Nokian Gazzaloddi just put this tire on because the trail got very muddy and the cranks 165mm mode this thing is monster now :-).
26x2.35 big apple only used this tire at the unicon for the 10km and 42km.

Hi rvs,

Nice setup you have there! So you seem to be quite happy with it. That’s an interesting solution for a handle. I’m not sure what I will end up with. Maybe another (crooked :roll_eyes: ) T7, or something custom made…

Is that the nimbus rim you have on there? I will probably get a try-all because I want to install maguras on mine. Not that I need them much here, but if I want to go riding in southern Germany or other hillier areas I wouldn’t want to miss them.

Maybe we could meet sometime and go for a nice muni ride? Do you know any more muni riders in your area? Would be cool to meet…

Yes , that’s right it’s nimbus rim.
I still have to make some kind of bracket for the maguras brake.
I know one person in the area that also do some muni ridding.
You life in arnhem??
That’s not to far from where i life Cuijk close to Nijmegen.
I do a lot of riding in the area of Nijmegen/Groesbeek. ( )
Last year we already had muni meet in this area ( )
I like to do a ride with you then you can try the 26" guni.
What kind of muni do use and where are you riding??

Hey Roland,

If I had to choose, I’d put it in a 24, but that is because I prefer offroad technical riding more than road riding. Basically I did have to choose, since I have only one hub at the moment.

However, I really prefer the geared 36 for any given long distance riding, since it is much more comfortable, and lets you cruise at a higher pace. I probably won’t do any significant long-distance rides until I get a geared 36 going again. (ie: I’ll keep it less than 30 miles, which is fairly comfortable on a 36, with the exception of the Africa uni tour, which I’m planning on doing on the geared 24).


Thread Jack: Thread Jack:

Sorry but I thought I’d ask here since I’m going to building up a KH / Schlumpf Geared 24" Muni. What lacing pattern did you use? Triple Cross? Quadruple Cross? Also what gauge spokes 13g? 14g? 12g? I was planning on triple cross with 12g as that is most common, but I want to build a bomber of a wheel so perhaps the quad is better? Thanks.

Ken Adelman helped me build the wheel (he really did all the hard work). I’m pretty sure you want a 3 cross – I don’t think you can get a four cross in there (there won’t be enough room).

I used 14g ss spokes; NOT the thicker 13 gauge that Kris ships his uni’s with. Ken figures that the additional thicker gauge spokes isn’t needed if you build the wheel properly, and I agree. So, why go thicker? It adds more weight that you don’t need.

Here’s what I got:

kris’s site say to use 227mm; I think I had mine cut to 228mm which ended up being about 1mm too long.