Internal Geared Hub

Hi All,

I was thinking of buying a 36" Coker for daily commute ride purpose due to its high relatively speed.
However, I don’t like the size of it so much and I would definitely want the 26" wheel size if I could have the right speed (as the 36"offers).

I did however bumped into one of the excellent tutorials of Terry Peterson on YouTube regarding the internal two speed hub for 26" wheel - which makes it run in ratio of 1:1.5 = virtual 39" wheel size!!! :slight_smile:

I was wondering about few things:

1- Is it truly in “production state” or is it still somewhat in “beta / testing” phase phase?
2- How hard is it to learn to use it - to switch between the 2 different gears.
3- What is the risk of getting jammed due to malfunction in the gear and how expensive is that to fix?
4- Would it work only on KH unicycle model or it can be installed in a different unicycle vendor as well?

Your comments are most welcome!


Schlumpf geared hubs are kind of a big deal around here. There is a list of “registered” owners here: Schlumpf hub serial numbers reference

A good place to start learning more about the hub is the Schlumpf hubs: general discussion thread.

  1. Production phase.
  2. Easy to learn.
  3. Low risk, if you properly set it up. Expensive to fix if it breaks due to your fault (not likely)
  4. Any 42mm bearing holder frame…but it works best with KH frames.


I agree with corbin, except on the Easy to learn.

For some people it’s easy, others not so easy.
My first season with a Schlumpf I found it hard to use.
I’ve had it 2 1/2 years now and it’s much easier, but still just a touch beyond what I’d label easy.

It’s been a lot of fun!

How easy are the things to maintain? I’ve read a lot of people mention oil and stuff. Do these require constant treatment?

My personal opinion is that the Schlumpf is not really an appropriate purchase unless you have a decent amount of experience doing long-distance road riding already. Or you have more money than you know what to do with. After five years, and thousands of miles, and numerous road and MUni races on my Schlumpf, it’s still not as easy to ride as an ungeared uni. And it took several hundred miles of practice just to get to the point where I was comfortable on it.

Depending on the length of your commute, a short-crank 29er might work. For up to about 3 miles I’ll take my short-crank 29er over my 29er Schlumpf every time. It’s still reasonable up to maybe 5 miles, after which it starts to get frustrating.

The oil stuff is simple
Half to one syringe of grease once or twice a year

There are some slightly tricky aspects to maintainance

Some of the bolts used for buildih it up / striping it down have torque limits. So it is suggested you either get some torque wrenches or torque control screwdrivers
Or get someone else to build it for you

I’m talking about crank changes and the bearing housings. I certainly don’t recomend opening the hub itself

I was a bit apprehensive of the maintenance to begin with, but it’s not too bad with some care and the right tools

Schlumpf hubs are pretty amazing.
If you have the chance to try one take it.

I’ve opened the hub up and replaced bearings too. It was pretty easy! (On a level of how hard things have been…I’d say it is easy with the old hub. You might need a bearing press with new hubs).


Yup, same feelings here, though I have far less Schlumpf time under my belt than Tom.

It helps to have access to one before jumping that train, it’s not all that great, takes a lot of time to learn, and even then it’s not perfect, but it’s the only geared hub going.

Of course that won’t stop me from buying one again :roll_eyes:

Corbin tends to forget that he’s not a normal human. Easy for him? Should be suspect to mere mortals. :slight_smile: That said, you can definitely ride a 1.5:1 gear on a 26" with some practice. Shifting at high speed, riding rough terrain, etc. may take a long time to learn, but that’s okay. Unicycling is supposed to be hard. I consider the Schlumpf Hub to open up a great area of “advanced unicycling” and I am enjoying the learning process.

They are expensive enough that you don’t want to get lazy and wait for it to break. So occasionally you have to add some oil, which is no big deal. More importantly, you have to torque things right. So now I own a torque wrench. It’s a good thing most unicyclists are nerds; we generally like such things.

I’d say go ahead and buy one if you can afford it. This fuels the system of unicycle development. The more hubs that sell, the more chance there will be of future innovations and possibly lowered prices. Meanwhile, if you try it and it doesn’t suit your fancy, you can sell it to someone on these forums at a reduced price! That’s how I got mine. :sunglasses:

Guys thanks a lot for your feedbacks!

I can’t help it but everything about the hub sounds great except for the price :slight_smile:

I’m sure I’m not the first one saying this, but is there a cheaper alternative?
Maybe some old models or OEM vendors, etc.

@One4All I have similar requirements to yourself and similar concerns about 36". I’ve been considering the Huni-Rex versus Coker instead of a Schlumpf hub however.

Have you considered whether a Huni-Rex meets your requirements?

At the end of the day though a Coker is simplest and cheapest, so I’m still on the fence.

The Huni-Rex is indeed interesting but I too would seem to either go for the Coker or 26" with short cranks.
The internal geared hub is way too expensive.

I hope I don’t upset people, but…

Personally–when I’m looking at these options for myself–I can’t get over the ineffciencies of planetary gears that I experienced on two wheels. Especially true in real cold weather. I also never experienced the Nirvana of “low maintenance” with them.

To be fair I always used mid-range IGHs and nothing closer to the price point of a Schlumpf (no Rohloff for me).

You won’t upset people if you go ungeared. I bought my geared second hand off of a friend who doesn’t like geared. He’s ridden his ungeared 185mi in 24 hours. He never felt comfortable on the geared.

I’ve found I like both the geared and ungeared 36" unis. Ungeared 36ers take a bit to learn, but are the simple way to go relatively fast. I personally am not the hugest fan of Cokers (the unicycle brand- not the wheel size). I think the move to ISIS splined cranks in a Nimbus or Kris Holm is worth it. Dual hole cranks are great too, and they mostly come in ISIS.

I love my ungeared 36 and still ride it regularly. I’ve got thousands of miles on it and it’s been pretty much maintenance free. I don’t plan on ever riding geared exclusively as I like the experience of ungeared unicycling.

As far as the cost goes for a Schlumpf hub, they are a hand finished small production Swiss product. Quality control is at the extreme end of the spectrum. Florian strives for mechanical perfection. He strives for a zero failure rate as he wants to see no one get hurt. There have been several voluntary recalls for product improvement even though there wasn’t a likelihood of catastrophic failure. Someone else can chime in on this- Have there ever been any that failed catastrophically under use (other than Ken’s) where someone got hurt?

The hubs are not an incredibly difficult design, but at 20mph+ on one wheel, there is no room for failure.

That being said, when they due have to go back into the shop it most likely will be a several month wait to get it back.

Compared to bikes, the price is relatively inexpensive. Go buy a high end drivetrain or a nice suspension fork for an MTB. Schlumpfs are to the point where they most likely will outlast both. As far as road bikes go, those drivetrains get expensive really fast too.

Yes, there is mechanical loss due to friction, but if you want to go faster in comfort than a 36" ungeared wheel will allow, it’s the option at this point.

And not a bad one in the least.

The Schlumpf is a bargain compared to a similar high end system on bikes, but it does seem expensive compared to a fixed unicycle hub.

A 36er is simple, fun to ride, and not that expensive. You should probably ride a 36er first before getting a guni, it might meet your needs and then you’re done.

I also contemplated buying an older model hub, but decided against it because they hold their value so well that unless you get a really old hub (square taper) you will not save much over buying new and you will not have the benefit of a full warranty.

The Schlumpf hub is always evolving, if you wait long enough you may even see one with a rotor mount, mmmm :smiley:

Damnit! Now I’m torn again! Sorry for thread-jacking, but I’m facing a very similar decision right now, and I missed this post when reviewing the Schlumpf-related discussions. After reading these comments, I’m seriously considering abandoning the Schlumpification of my KH29 and just snagging a KH36.
Again, apologies to the original poster, but I too would really appreciate some input from the very knowledgeable contributors to this thread.
I started riding last summer and am now at the point of regularly commuting (24-mile round trip) and touring (up to 30 miles) on my 29er. I know I can squeeze some extra performance by doing such things as going to the inner crank hole, using a road tire, fitting the t-bar, etc, but by next summer, I want to be logging three or more times the milage I’m getting now. This obviously requires a more dramatic shift from my current setup. I want to flatten the impending learning curve as much as possible, and I thought the way to do that was by gearing my 29er. On the other hand, the 36 isn’t just faster, but also looks like bags of fun in alot of ways unrelated to pure performance and efficiency.
I’m giving myself one more week to decide, then I’m either going geared or popping for the KH36… Thanks TONS for what you’ve already contributed, guys, and any additional input that might help me make my decision would, of course, be very gratefully received. :slight_smile:

This much is unequivocal: Riding a geared 29er is harder than riding an ungeared 36er. For some people it’s a lot harder. Do not buy a Schlumpf because you think it would be easier than a 36"; it’s not.

That being said, if you’re currently doing 30 mile rides, and want to ramp up to “three times” more, I think a Schlumpf 29er is possibly worth it. To enjoy even 30 miles on an ungeared uni takes a certain kind of personality and attitude; more than that takes a certain kind of madness.

Yeah the 36 is a ton of fun
Recently bought my first 36

But it just like the schlumpf has some difficulties. Mounting, carting it about and storage

The schlumpf brings some unique challenges adds an extra dimension to riding and is also an absolute hoot once you get the hang of it

For me a schlumpfed 26 gives 2 very usable gears. But that’s a whole other debate

They are both amazing, fun, and challenging in their own way. Basically you need both

I just recently got myself a KH29" shclumpf. I’ve been riding a 24" learner since june 2012. With no real practice on my 24" the last two months (it broke), I adjusted quite fast to 1:1 riding on the 29. Fremounting no problem. However, the first session in 1:1.5 I couldn’t even ride 1 revolution. Day 2 I got to around 40-50m and struggeling the whole distance. I should also mention you have to be fit to be able to ride 1:1.5 (Whats the virtual size for 29" schlumpfed?).

However I am not in a hurry to go fast, I want to have fun. Gears puts you back to square one (maybe two), but its really fun and rewarding when it clicks. For now 1:1 is way faster than my old 24" and I know with practice 1:1.5 will be great whenever I need it.