Schlumpf poll

If you had one Schlumpf KH geared hub, would you have it built to a 24, 26, 29 or 36.

I am thinking 26 Muni or a 36 for speed but I have never ridden a geared hub uni.

This isn’t really a poll, do you plan to make it one?

For the kind of riding I do, mixture of some easier XC and tough hilly and technical single track interspersed with sections of gravel/paved road, I really think my 24 GUni with 150mm cranks is ideal. The low gear with this crank size is pretty good for all the buff trail riding and in hi-gear I can still ride some of the easier XC (like a 36" wheel) and with the added KH touring handle bars I can get spinning pretty fast on the roads. For me, a MUni wheel larger than this would be great in low gear on trails but for me probably almost unrideable in high gear though would be wicked fast on the roads… So it’s a trade off, but since most of what I ride is fairly technical it’s a reasonable compromise for me. The obvious downside is that, as countless other threads have stated, the tire 24" tire choices for MUni are dwindling. I’ve got some 24" MUni tires stashed away that will last a while, but I realize that I’ll have to go to a 26er someday unless there is a resurgence in 24" off road tire choices…

I have one and it’s in a 29er with dual-hole 125/150mm cranks. It’s an extremely versatile setup; able to do long distances at race speed as well as fairly serious MUni.

But it depends on the kind of riding you want to do. If it’s mostly MUni, I’d do a 24". If it’s mostly road, I’d think about a 36" (although I still hate the weight).

I have the same set up as Tom (g29 dual 125/150) and agree completely it is great on singletrack and great on the road, just need to swap out the tire and change the pedal hole.

If you do a search you can see one of my updated threads on the differences and thoughts between my experience with both the geared 36 and geared 29.

I would say, however, if I wanted just a geared muni I would rather have a g26 instead of g24 - not based on any experience on either, but I think the 26 would give me more tire options and I would like the feel better than the 24.


I have a 26" Schlumpf Muni :slight_smile:

Probably a 36, but really I’m waiting until we get some more/higher gear ratios (maybe 1:2 or even 1:2.5 as well) before I bother spending that much on a hub!

You can’t get 1:2 with the Schlumpf design; you probably can’t get significantly higher than what we currently have (1:1.54).

To reiterate what tom said:
The answer is highly dependent on what riding you like more. Road riding? Then a geared 36. Muni? Then a geared 26 (or 24 – they are almost the same).


Well, because I’m an ugly American I subscribe to the attitude of “bigger is better. BIGGEST IS BEST!” Therefore I have my Schlumpf in a 36. I love it. I go fast. I go long. Marathons, centuries and even some tricky trail riding. Not technical muni with rock hopping and big drops, but tight twisty trails. When I get rich enough to squander another chunk of change, I’ll buy one for my KH 26.


If I had to choose one wheel size I would go for a g26, which is what I got first before I got the g36. The 24" and the 29" must be great as well, but I think the most versatile one is the 26" with 150mm cranks. Put a muddy mary 2.5" freeride on and it’ll be great for the trails. Add a KH t-bar for added comfort on longer tours.

Please don’t; it’s a waste of time (no useful meaningful statistical data will be collected).

Sounds like you haven’t ridden one yet. 1:5 is a pretty good ratio for a unicycle. Higher makes the riding increasingly tougher! Not the pedaling, the balancing. It’s like making your balance envelope smaller as the ratio goes up. It’s small enough at 1:5, though this should be less of an issue with smaller wheels.

My chosen size was 36" I was going to go 29" but Nathan Hoover convinced me 36" was the way to go if I want to do long rides. It can still be used for MUni (mostly in low gear), but it can crank out the miles on road. If I were to get a second Schlumpf, it would probably be on a 26" wheel, and focused on MUni. :slight_smile:

I was under the impression that at higher speeds balance gets easier?

Regardless, I’d like to see some higher gear ratios experimented with. I’m curious as to what the top flat surface speed possible on a unicycle would be while still in control.

Things are more stable at high speeds. Going 30kph on a geared uni is a lot more stable than 30kph on an ungeared uni. (Just ask Beau Hoover to show you his scar).

On the other hand, getting up to a reasonable cadence in a high gear is difficult on a unicycle. Some guys like Chuck and Corbin can just mash their way up to speed, but many folks need a tailwind or a downhill to really crank a big uni gear at speed.

We’re starting to go fast enough that our crappy aerodynamics are coming into play. I estimate we’re about 20% less efficient than bikes, as a combination of aerodynamics and wobble.

For me, I can crank a bike up to a bit above 50kph on the flat; correcting for unicycle inefficiency, I think it translates to 38-40kph max flat speed on a uni, for me. That’s actually not a whole lot faster than I’ve personally gone already; it’s perhaps 2-4kph above my best known flat speed.

So, we’re getting closer, but still have another 20-30% we can squeeze out of better equipment.

This is what I’ve been thinking. Lighter frames, better aero posture like the designs ebevensee has been experimenting with (and my avatar, which seriously reduce wobble), possibly thinner wheels, clipless pedals to again reduce wobble and make a more efficient stroke (some people swear by them) etc. will probably aero things up enough for higher gears to work. Then we can really see how far things can be pushed. The bicycle hour record currently sits around 56k - I can see us hitting 45 eventually.

Anyways I really need to put my money where my mouth is. I’m keen to build a T frame 36 Guni at some point and see how it goes. It also seems there are disk brakes out there that now work with schlumpfs?

I think some of those things are right, but some are a bit off.

Frame weight? Makes no difference at all to flat speed, and negligible difference to hilly riding.

Better aero posture? Big difference - this is where we can improve probably the most. Getting our shoulders down to give less of a wall to the wind will make all the difference.

Thinner wheels? Would have a very small effect on aero performance, but would mostly be used to reduce weight, which makes little difference to flat speed record riding.

Clipless pedals? I don’t see how they reduce wobble, but they do give better pedalling power. Certainly a potential benefit if you get confident with them.

Probably the biggest asset would be really powerful legs, honed on years of racing bikes. That was how Chuck smoked most of us.

The Schlumpf ratio of 1:1.5 is pretty good for us now, as even at about 32kph with 150mm cranks I feel it is almost perfect cadence, like a bike. It only starts feeling a bit too spinny near 40kph. So I don’t bother with going down to 125mm cranks. Slightly higher gearing would work too, but 150% works pretty well.

I’m poor at forecasting, but I really struggle to imagine the Hour getting to 45km. But it can go 35+.


Hi Mal,

I’ve had my schlumpf for about 9 months, and originally I built it into a KH26. I took this uni to Mongolia, mostly because I was travelling a lot after the tour and lugging a 36er around 3 continents is not too fun.

The 26guni is a very versatile uni, and worked really well during training and during the Mongolia tour. For off road GUNI, with some smoother faster sections, I don’t think it can be beaten. The terrain in Mongolia wasn’t too extreme, and I was riding with 125mm cranks for the entire tour. There were sections were with 150mm cranks it would have been easier, but all round, 125mm worked really well.

However, on the tour I spent some time riding a KH36 guni, and after spending two uni tours watching the Hoover’s and other 36er GUNI’s fly past me, I have decided to build my hub into my KH36. I got home from my travels on Wednesday, and by Thursday afternoon my hub and rim were at Kaos Custom Bikes in Melbourne to rebuilt as a 36er GUNI. I am picking it up next week, and am looking forward to some fast cruisin on my new speed machine.

Also, I second what John Foss mentioned, in low gear on a 36er with 150’s, you can still ride a lot of muni stuff.

I’ll see how the 36er goes, I have been toying with the idea of getting a second hub. If I enjoy the 36guni as much as the 26guni, then I might build up a 26GUNI again in the future. See how the cookie crumbles. :smiley:




On weight you have a point, though less weight does = less ground friction. Aero - yup. At 50kph something like 80% of a rider’s effort is fighting the air. Sitting upright on a uni this must still be quite high even at lower speeds. Wheel thickness - this is more about roll resistance. The smaller the contact patch with the ground, the better (while still having enough to grip).

Clipless pedals reduce wobble by evening out the stroke i.e. having power throughout more of the stroke rather than sudden. That = less wobble. Another big thing that reduces wobble is of course the posture, by holding onto the elongated front of the frame you’re stopping most yaw wobble.

On cadence - I don’t know a whole lot, but I read somewhere that on bikes the best cadence for a record is about 100. If you take their speed and translate as though they were on 36 inch wheels that works out to about a 1:2.6 ratio. Since we wont be going that fast on a uni maybe 1:2 would be heading the right direction? I dunno. There are probably a bunch of other factors involved.

OP - sorry, I think we’ve hijacked your thread…

Hahahha, sure you can ride muni on a 36er, maybe some easy double track, a little rolling gravel hill, but single tracks with twists and curves, not!

In an ideal world we would be able to afford a geared hub on all of our unis, in which case I’d have a 26Guni, 29Guni, and a 36Guni. BUT, the reason these conversations persist is because a geared is sooooooo expensive that most folks can own one at most.

If you want to ride easier single track, a 29er is about as big as is reasonable.
If you want to ride technical single track, a 29er is possible, but a 26 or 24 is more appropriate.
If your muni consists of gravel and dirt roads, but you mostly ride on smooth surfaces and want maximum speed, a 36er is an okay choice, though a 29er may be a better choice down the road so you can do more technical stuff.

If you can’t choose, then build two, a 26 and a 36.

If you really want to go fast, get a bike :wink: