Oh and I want a hand shifter too
As a new Schlumpf owner, me too!
with a single gear train, if up gear is 1.5, so down gear will be 0.67
0.67 is really too short even on a 29"
my design is a 3 gears hub 0.727:1 / 1:1 / 1.375:1 and with twist shifter.
This is the best compromise I found for a 29"/125mm cranks on off-road or a 36"/125mm on road
Tom, do you remember that 36er I was showing off at the Cali Munfest? It has an Oregon hub that is a pound heavier than a standard hub, and yet everyone who rode it didn’t seem to notice, in fact they seemed to think it was more agile than a typical 36er.
As far as insane, well, we ride unicyles, so that really doesn’t apply to any of us as we are already insane 
It looks like there are at least three people who would like a geared down hub 
I think adding a geared hub to a 36er in order to go faster is insane, so take that!
transmission efficientcy for different bike hubs, 3 gears even with lower efficientcy is better than only 2 gears :
I’m talking about the rim and tire weight (as I noted above). The only reason unicyclists ride big, bulky 36ers is that prior to having gearing, that was the only way to get an effective gear ratio above 29". It is insane to ride a big, bulky wheel to gear it down.
Tom, that is not why all unicyclists ride 36ers, that’s why YOU ride 36ers.
I ride 36ers off road because I like the way a big wheel feels, it’s just plain fun to ride a big wheel on technical terrain. I also find it challenging to ride a big wheel on a trail better suited to a smaller wheel, esp if that trail has become “too familiar”.
But, I find that the big wheel is effectively geared so tall as to make some climbs too difficult, so a downgeared hub would be nice, esp if that step down was a more reasonable 25-30%.
I believe there were some folks riding 29ers on Sandia and I didn’t notice them struggling any more than the folks riding 24-26" wheels, so maybe bigger wheels are okay…like it kinda depends on the rider’s preference 
I don’t ride 36ers.
You can get the same challenge by riding a smaller wheel, geared up, and leave the extra two pounds at home. And then you don’t have to choose your car based on whether it will fit your unicycle.
Considering that the two people who walked out due to injuries (Friday and Sunday) were both on 29ers, I’d have to say they were struggling more than the smaller-wheel riders. And I am personally massively glad that I didn’t bring my 29er, which I’d been considering. There’s no way I would have ridden anything near the stuff I did if I had the 29er.
I’ll admit that I am suprised that you don’t ride a 36", but then that would explain why you didn’t take a 29er on the Sandia trail and why you are more inclined to upgear a smaller wheel.
I rode a 29er on the Sandia trail and did fine, but then that’s what I’m used to riding, so I suppose the same goes for my desire to ride a big wheel and have a downshifting hub.
To each their own, fortunate for you and yours, an upshifting hub is available, so for the moment my downshifting insanity is entirely theoretical.
Getting off early today so I can go do some “insane” 36er trail riding 
I don’t think anyone who rides big MUni took a 29er on the Sandia trail. Josh Schoolcraft and I both ride a lot of 29er MUni; both of us brought 24" because we would have been skipping the fun stuff if we brought 29ers.
You missed the Friday trail where that was even more true.
For long road rides, like centuries, I would vastly prefer an ungeared 36er to a geared uni of any size, especially anything smaller. For XC to moderate tech MUni I much prefer my G26er to an ungeared 36er; and a G36er for trail riding is massive overkill, imo. My G26er is super easy to climb in 1:1 and handles very much like a standard 24 or 26er, and in High gear it’s faster than my ungeared 36er. And because I’m not as high off the ground, the handling in high is much more stable and controllable than with a 36er.
So you ride a 36er because it makes easy trails more of a challenge, but you want to gear it down to make them less of a challenge? 
Not exactly, more like: I enjoy riding my 36er fast on trails that no longer challenge me on a smaller wheel, kinda like the inverse of folks who want to take a small wheel and gear it up for places where a small wheel is too slow and easy. It’s just a diffent way to approach the same problem.
Funny how 36er riders regularly discuss the difficulties of sustained climbing and steep hill climbs due to the relatively tall gearing with a big wheel, but when I discuss a geared down hub it is ridiculed. Personally, as a 36er rider, I have no interest in riding fast, but today I had to walk a long steep uphill that I couldn’t ride on my 36er, but if I had a low gear option I would probably have been able to make the climb. It’s what gearing is for, to help the rider achieve greater performance, so how is that insane?
And yeah, I could have rode a 29er or a 26er in order gain that hill, but then the other 90% of the ride was a mix of gravel road and buff single track which were well suited to a 36er. Would I have ridden a 26/29 guni on this trail, nah, this was some terrain that was better suited to a big wheel where I could roll fast and smooth.
So my question for other 36er riders is whether they would choose to have a geared down hub, so would you?
If you’re asking me, I’ve never ridden a 36er - still a relative novice having only been riding a year. Have just bought a Schlumpf 29er though (which I nearly bought when I’d only been riding for 3 months 
)
From a geared hub, I would like the gears 1:1, 1:1.5 and 1:2.
No granny gear on my uni:D
And I would like a hand shifter.
And a bit of topic: I would like to have crank lenght adjustment while riding.
I guess there are a lot of mechanical engineers (like me) on the forum, could it be done?
A range from 115 to 165 mm, in three or four steps, shiftable by hand.
Preferably a simple and reliable solution. I need to convince my boss that we can make a project of this.
My advice… If you have a passion for unicycling, and a want to add speed at your current wheel size, then don’t let any of the possible negatives keep you from getting a Schlumpf now.
Don’t waste time waiting for a better hub to appear. You might end up waiting years, only to finally settle for a Schlumpf. You’d have been better off getting it earlier.
It took me like a year to get comfortable with it, but I absolutely love my Schlumpf and take advantage of it all the time.
I ride a 24 guni. 24 because climbing hills and succeeding is what I love. But when I encounter a flatter section, shifting up to high gear feels so enabling. If I liked to ride muni on a 36er I could totally imagine how enabling a lower gear would be when I encountered a hill. And with the different feel of different wheel sizes, it makes sense to me why it would be desirable.
Some things I’d like to see in a guni…
- 3+ speeds
- hand lever shifting, especially if we have more speeds
- maybe the modular/swappable/shell idea
- lighter weight
From my limited experience trying Tony’s geared 26 muni I think Schlumpfs are fun, but really expensive and I’m not sure how often I’d take a uni with one on a muni ride. I cannot imagine spending that much money on a hub anytime soon, but later on I think it would be great to try one out more seriously- hopefuly by that time they will have advanced somewhat!
I guess my short experience (~1.5 hours or so) is not enough to really have much of an oppinion on a Schlumpf, but I think it would be great if they were less expensive, much lighter (say like 800grams) and more reliable/stronger but those are 3 difficult things to do haha.
You’ve not heard of Tom Ritchey’s maxim, “cheap, light, strong, pick two”? As for the weight, a standard uni hub is 600g - an 800g geared hub is fantasy stuff.
I think the “Strong. Light. Cheap. Pick Two.” is a Keith Bontrager quote.
That doesn’t make it any less true. Or lessen Tom Ritchey’s contributions to cycling.
You’re right of course :o