KH-Schlumpf geared hub will be at Fluck


Here’s an update on the KH-Schlumpf hub.

The intent was to make a geared hub with ISIS spline that’s good for both on and offroad riding. Here are the some of goals we had for this hub:

-Standard 100 mm bearing spacing with flanges as widely spaced as possible,
-1:1 or 1.5:1 gear ratios
-ISIS spline axle and internals strong enough for offroad riding
-Snappier, easier shifting with improved round shifter button shape and a stronger shift rod and bash-resistant shifter system
-No requirement for a lever arm bolted to the saddle frame, replaced instead by a knurled 42 mm sleeve over the right bearing. The bearing clamp becomes the “lever arm” required for gearing- no need for bolt holes in the frame.

Removing the lever arm makes the hub fit in any existing KH frame sold since 2006. For earlier KH frames, the bearing housing lips must be ground down to 2 mm height for it it fit. This also allows the wheel to be flipped to allow the rider to choose their preferred direction of button movement for shifting.

I’ve been working on this for 2 years and have tested it on a KH24 and KH29, including North Shore trails with drops up to 2 m, XC trails and road riding. Attached is a photo of the result- the final production prototype built onto a KH29.

It’s an awesome ride. The gearing allows you the same riding you’d have on a regular uni, plus 36’er - like speeds once you hit easy trails or road sections. And you can almost keep up with the bikes on road commutes to the trailhead! Weight is 1420 g, heavier than the Moment hub but surprisingly not that noticable. There is slight back and forth looseness when you idle but you don’t notice it after you’ve ridden a few metres. With ankletop shoes, shifting is easy and instant once you’ve practiced a bit.

For road touring you get the speed of a large wheel with the hill climbing ability of a 29’er. Stability is slightly less than a 36’er. The 125/150 cranks seem ideal because 125 seems (to me) to be the ideal length for road riding.

Regarding limits to the use of this hub: It’s not possible to state limits on, say, drop height with this hub, due to differences in rider skill, weight, and style. With the level of testing it has had so far, I personally would use the geared hub for all kinds of offroad use, but I would stick with a regular splined hub for pure agressive technical riding.

We’re starting production but lead time on getting it to stores is still long (on the order of months). I’ll post further about availability and price once that’s worked out.

A geared KH24 will be at Fluck for anyone to try.


that’s really cool! I wish I was going to FLUCK. Kris, are you going to NAUCC?

wow, that looks awesome.

that looks pretty sweet.

I should add that it does not replace the current Schlumpf geared hub, which is lighter and intended for road use.

OK gotta go for a ride…


Will you be offering a 36" version?

it’s the HUB that’s being offered. you’ll be able you put it on any frame you want, as long as it meets the specifications Kris mentioned. Whoever you choose to buy from (Florian Schlumpf or a reseller) would most likely be able to provide it to whatever spec you require.

See you Tuesday!


Sweet deal kris. Im pretty sure Ill be gettin one. Having this hub opens my mind to so many new places to ride…and you can ride trails in a descent time. Now when I ride with mountain bikers, it wont be as painfully slow in the longer, flat sections. Keep up the good work Kris! Ill be looking forward to riding one!

hey Kris
any word on the final price? I’ve heard all kind of rumors, and just want to know if its something I can save for or something I’ll just drool over.

I think about this hub damn near everyday.

I hate the idea of getting a large Coker, but
most of the guys here ride Coker now, and
I ride a combo of distance and muni.

I’m looking for the durability to handle my weight and strength.
I’m hoping the gearing will allow me to keep up with the Coker.
I’m looking forward to the durability and portability of the wheel.

Please put me “in line” to purchase one of these hubs.


will you be sticking with somwhere near the estemated $1600 for the KH24 with geared hub?

next thing i want to see:KH36":smiley:

Regarding the price. I don’t know that yet. It will be fairly similar to the existing Schlumpf hub and assembled uni.

The hub is shipped separately to dealers so you could order it separately or built onto any size wheel you want.

Mike Penton: I can’t go to Fluck. I want to go but unfortunately I have a geology work conflict, which really sucks. That’s the problem with having 2 careers at the same time- fun work but they get in the way of each other sometimes.


dude, that hub looks great, but if you did a rolling hop wouldn’t your front foot hit the button?
I obviously havnt ridden it, but that seems to be my only concern.

Normally I’d have some sort of knowledge on components quite sussed, however this is rather different! It does look fairly promising though judging by paper description. From an aesthetical standpoint it does look really cool as well, especially with the way the hub flanges are shaped.

Hmm, now if only Moment hubs came in black with the Kris Holm signature on it like on the KH/Onza or KH/Schlumph hub, that would look great.

However, it is always great to see the fruit of the labour. Collaborative side-projects are definitely great fun to design and talk about with your partner(s), especially to have it finally made into a physical solid piece of gear. Perhaps I should post up pictures of the Triton later on?

Anyway, it’s great to see another breakthrough product, the hub sure does seem promising. I wonder how it’d perform for some curious street riders? Perhaps change it to a harder gearing when trying to gain speed for rolling hops and speedy grinds? I’m not too sure, but meh, could work maybe. (for some people)

Sweet! A unicycle with KH/Schlumpf hub and double hole cranks has effectively 4 gears. That should prove to be very versatile!

Wowwwww. I got to get me a summer job…

Amazing. I’m glad to see this is done, although it’s going to suck to go riding with those who use this hub, simply because it’s going to be so difficult to keep up with them…

Judging from what appears to be a relatively short throw of that little shift knob, the shifting innards of that hub must be pretty thin. Just a guess, you have two or three layers to the shifting mechanism to help distribute torque without having to increase shifter throw to accomidate wider gears? If so, I give you even higher props, as the innards have to be damn precise to do that.

This is totally off topic and I apologize for it though I was wondering if there has been any changes to the KH 20" for the batch UDC will be getting soon.

This new geared hub looks excellent, its definitely something I’m going to have to consider in the future.

Kris, your not going to FLUCK?
That sucks :frowning:

Peter M

looks awsome! Did it get tested on drops above 2m?