This is a 3 speed square taper setup that is a specific make and model. a dude bought a bunch and can mod them to work on unis. he had a CAD image of the modified guts… wish I copied his posts and not just the image…
I don’t much like the idea of chain systems and unicycles. What happens if you’re riding along and your chain breaks?.. SPLAT
Bikes can deal with that happening, uni’s… well…
the sram setup would work with an ISIS jackshaft…
That is Frank Bonsch’s project. You seem to be posting a lot of links and videos. They’re pretty but, in and of themselves, contain no real useful design information. I wish you had read his posts…don’t worry about whether or not you copied them. Frank’s hub was not a square taper axle setup. The modification that he did was extremely complicated and time consuming. The final product is a single speed hub, not a three speed hub. The square taper axle he had machined with a multi-point boss for pressing the planet cage on rather than welding it was a particularly complex part of the conversion.
You’re posting pictures of stuff that many of us have seen before and discussed in great detail. Just because there is a photo of something doesn’t mean that it was cheap or easy to do or that it is in any way practical to implement on a unicycle. It’s not strictly the case that “a dude bought a bunch and can mod them to work on unis.” I can assure you, Frank is not going to make another one of these.
Damn sad that there will be no more of those hubs. It was a 3 speed conversion, sorry didn’t try to say it was a 3 speed hub, but you’ll forgive that. I like pretty things and hope to share more. I am glad that you read the posts that I had, and I’m impressed that you remember the discussions, even lengthy ones that I have since forgotten the details of, (I am impressed;)). I do apologize for my short memory and the nature of repeating threads, this is an inevitable result of new blood. (“what kind of Uni should I buy?”)
You should probably avoid rehashed posts if you are uncomfortable with them, although your insight is indispensable as you are well read on the subject matter. My posts have been on topic regarding belt drives, jack shafts and gearing products, and there’s nothing stopping me (well except cash flow) from incorporating the things I have posted into a geared unicycle -including a CSV possibly. I hope you can help me to remember stuff, and that I may help you realize old ideas can take on new life -even if it’s not yet apparent to whom these ideas have simply worn out. I am not apologizing to you again.
Lastly, not once have I claimed that “Just because there is a photo of something doesn’t mean that it was cheap or easy to do or that it is in any way practical to implement on a unicycle.” practical is a plain unicycle… that is obviously not the nature of this thread.
BTW: What is the standard of “design information” required?
Its not a mather of blaming each other but you could have read some more info about what your posting…
There where a couple of schlumpf like hubs.
like the one harper made http://staff.washington.edu/gharper/
Take a look at the drawings and you will see thats it is a complicated product
only drawback is that you can not shift on the fly.
But the biggest problem to solve is to learn riding on a unicycle with a freewheel, then a unicycle with a lot of gears is simpler to build.
excuse me for my englichs not my first Language.
Tell ya what, you learn and let us know how that goes 
It’s not riding with a freewheel that’s the problem, it’s freewheeling in motion that’s the problem. Without some form of resistance, as soon as you freewheel you no longer have any way to create fore/aft control other than apply the brake or apply pressure to the pedals.
Notice that folks who practice coasting will do so with a foot on the tire, which gives enough resistance to balance aft while gravity and forward/downhill motion balance fore.
Freewheeling on a geared 36" uni at speed (20mph), now that would be brave, very, very brave 
Has anyone talked with the Schlumph designer about limitations to creating a three speed hub? I’d be suprised if he didn’t have some ideas…
well there whas a time that i thought riding a unicycle was impossible.
i’am not shouting something out in space without trying it myself.
currently i’am working on a jackshaft type geared unicycle.
I already had a try on a jackshaft unicycle with fixed gearing.
And that one was already very very difficult to ride because the chain tension was not perfect. so i know what i’am talking about.
so perhaps it is impossible but only one way to find out
thank you for that link… awesome!
please post pics of your progress!
I’m with sask - a bit of a look into these S3X hubs makes me think they could work, if not beautifully then at least usefully for unis.
A bit of a review here Sturmey-Archer S3X - Page 3 - Cycling UK Forum says that the shifts are clean (i.e. without much of a torque drop out, which feels odd for a bike, but is just like Schlumpf riders are already used to), and that the slop isn’t too bad. Schlumpf hubs also have a little slop, but for road riding it matters very little as you are pushing forwards almost all the time.
The ‘direct-drive’ of this S3X hub is its top gear, which makes it the smoothest to use. That’s also a plus - it doesn’t matter if the climbing/starting gears are a little, um, textured; as long as the cruising gear is nice.
And also with a jack shaft and chain you could have whatever top gear you like by varying the sprockets (you’d loose having a 1:1 bottom gear, but I don’t think that’d be a loss). And you can have a disk brake no problem (if Red Menace is anything to go by).
Very attractive proposition!
Sam
Okay. You imagine heavy. This does not mean not to attempt it, but is one of the problem areas that’s hard to get around. Also you have to contend with chains up around your crotch, when they’re bad enough down around your ankles. 
I’ve ridden a fixed-gear cycle like that; a Schwinn 20" geared to 40" equivalent. Hard to ride, of course. Not as noticeably heavy, partly because it was a Schwinn to begin with, and secondly because the cycle was meant as a novelty rather than an efficient transportation device. BTW this was at the Unicycling Society of America convention in 1982.
Plus a hub. I still think it would be heavy, but that really depends on the particulars. I guess you also have to include all the mounting hardware that holds everything against the frame.
Interesting. Can you say carpal tunnel? But I’m sure there is something available that can do that job. Connect it to the shift mechanism, and it might be able to be mechanically “lessened” during shifting if necessary.
In my experience, which is very limited, chains usually only break when you apply tremendous force, or when you make a bad shift. This is less likely to happen at cruising speed, and much more likely to happen when changing gears (slow), cranking up in the high gear (relatively slow), or backpedaling on hills or in an emergency (maybe not so slow).
Could be a shaft drive–in fact, shaft drive may be more appropriate for a uni, because it should have pretty close to zero slop. More weight with a shaft, but no chain or sprocket to eat your skin.
I’m not sure about that. A shaft drive would need two sets of bevel gears to get from the horizontal axle to the vertical shaft to the horizontal gearbox (although I suppose you could have a vertical gearbox and avoid one of those right-angles). I can’t help thinking it would be easier to get rid of slop in a chain drive than in a geared shaft (and more efficient).
I agree a shaft would be tidy and less likely to tangle with the rider’s appendages though. You could even make a vertically-mounted gearbox with two concentric drive shafts if you were being really fancy - that would be extremely tidy (if it could somehow be made small enough it could be pretty much part of the frame leg). How cool would that be?
Rob
Ah I was very much thinking about muni, which I would think would put a lot of pressure on a chain system.
I didn’t think about road riding really. Whoops!
Cool Idea
Hey Riverman,
That is a pretty good idea. Maybe you can cut down on the weight some by having the shaft actually be the side of the fork? Just a thought.
Also I have seen a three speed internal hub being sold for BMX bikes. From what I remember they are direct drive.
Check out this ShimanoShimano 11 Speed Internal Hub. It probably freewheels but there are some pretty interesting things out there!
Unicorn