And a photo of the new KH:
No no no!!!
I think the stability of the wheel comes more from the diameter (and maybe the volume of the tyre), not the weight. But I would give anything to lighten the wheel by 50%. It is VERY heavy! THe first thing I’ll be doing as an upgrade is to go tubeless, followed by shaving the tyre.
Ken, its the hub which is the heavy component in your wheel. KH-schlumpf hubs are really heavy! And there ain’t that much you can do about that. (Maybe a Ti axle upgrade option to make 'em even more expensive??)
I can see that a GB4 handle would be too short on a Schlumpf 36", but I disagree with your reasoning as to why a longer handle would be better. I’ve found that the T7 is good precisely because you are sitting somewhat upright. Particularly in those situations where you hit a bump or get out of balance and suddenly have to pour on the power in order to stay on. Here having a T7 is good because you can haul up on it really hard, giving your legs more to push against to apply the required power. I can’t help thinking that if you were super stretched out (with a Dustin Schaap-style boom handle) that it would be really difficult to pull up sufficiently hard to stay in the balance. It seems hard to imagine that you’d have the same amount of leverage as on a T7. I’m not a bio-physicist so I could be wrong here. I also think the resulting crash with a long boom handle would involve more skin loss as you’d be in less of a position to run out of a crash.
While this is only one situation where handles are useful, any handle for a Schlumpf has gotta be strong enough to haul on, much more than ungeared coker handles, which can act more as extended hand-rests. That is, unless its on a dedicated track- and flat-roads only geared unicycle.
Thanks for the extensive review Ken.
I don’t think that superlong cranks is a good option. It might be good for uphills in high gear, but you would lose spinning speed on the flat and essentially defeat the purpose of the geared hub. The TGR with 170 mm in high gear is only 4.16, the same as with a fixed 36" with 110 mm cranks.
Yep, the hub is the heavy part. But so is the rest of the wheel. Of course, for a 36" wheel, less the hub, it’s pretty good. But that doesn’t mean it’s adequate. All current 36" wheels are heavy. It’s just that with a bigger gear, you notice it much more when trying to accelerate/decelerate.
Basically 36" wheels really need to drop their weight in half to be competitive with bikes. We’re still a few years behind in technology.
Absolutely disagree with you there. The times I have used a T7 handle, I have been tucked down, trying to go fast, but my hands are up against my chest. There is no way you can get leverage or have any kind of speed when your hands are cramped up with nowhere to move. Having a lower handle let’s you straigthen your hands a bit more. I’ve found a T7 is like riding a bike with the handlebar up against your chest. If they flipped upside down I would probably get one. Or the best mod I’ve seen is Scott Wiltons roadie style extensions on a T-7.
See my comment regarding V-frames. I think the extension handles are getting ridiculously long with nothing supporting them. It would be like building a bike with a missing down-tube and seat-tube.
BTW thanks heaps for sending down the frames and for building my wheelset. The wheel felt stiff and was perfectly true right out of the box, and also after much twisting with the frame #1 debacle.
I think it depends on how much power you can get in high gear also. I’m not very fit at the moment, and I found myself itching to spin faster the whole time. I never felt myself coming close to spinning out at any time. So, in my case, I think longer cranks would let me spin faster. OTOH, if I was fitter or a stronger rider, I’m sure the 145’s would be adequate. I need to do a bit more riding to make up my mind.
I forgot to post my overall impressions:
Weight***
Speed *****
Quality ****
Stiffness****
Build**** 1/2
Shifting ***1/2 (I’m sure this will improve in subsequent models, so not a full 5 stars even though it’s the best shifting hub and wheelsize at present)
Ease of use *** (The buttons are fiddly and I’m pretty sure I rounded one of the little bolts which is why my shifter is stuck)
Cost **** (it’s good value compared to what you’d pay for a top end bike)
I liked the ride, and certainly it will be great for some of the bike races and unicycle races I do. It’s probably the fastest road unicycle out there at present, until I get a V-frame built anyway 
It probably will never be my everyday unicycle or touring unicycle…the 36" wheel is far too big. I ride a 29" Unguni for that.
But if you already have every other unicycle, then you need to add this to your collection. It’s a must have.
You may be right, but I’ll tell you what happened in my case. I tightened the little bolt to much, upon which the tiny allen bit snapped. The tool, now lacking the narrow ‘top’, did hardly sink into the hex hole of the little bolt. It felt as if something was rounded but actually it wasn’t. Florian sent a replacement bit for free, and that worked. So, make sure your allen bit is unscathed.
It’s actually both. The inertia is in some way related to the mass of the wheel at the radius where the mass is located. If all of the mass were located at the wheel radius the moment of inertia, I, would just be the mass, m, times the square of the radius, r^2.
I=mr^2
The moment of inertia increases quadratically with radius and linearly with mass. Realistically, mass also increases linearly with radius since the bigger the wheel gets the more rim and tire you have to add. All other things remaining equal, a wheel of twice the diameter will be twice the mass. Were this exactly true the moment of inertia could be expressed as a constant, k, times the cube of the radius.
I=kr^3
A 36" wheel set with the same tire and rim density as a 29" wheel set would then have a moment of inertia that is 1.9 times as great although the diameter and mass are each only only 1.24 times as great. We both know that the rim and tire densities of a 36 are much greater than a 29 so the moment is that much larger.
Regardless, the 36" wheel makes for a qualitatively stable ride.
A little amonia could have broken that seat post free I bet.
Yes, but I think it’s not just the inertia that contributes to the ride. I think the bigger diameter let’s you roll over bumps easier, and the big volume tyre also helps. That, and the bigger gear/resistance gives it a more bike like effect. Not the fact that it’s a beast of a thing to wrestle with.
Jagur…good to see you back on the forums.
I know you tried many ways to get that seat post out. Did you try inserting a piece of steel tubing-maybe a tad smaller than the diameter of the seat post-and pound it out from the bottom?
The bottom is sealed.
Basically, I’m sure it can be gotten out. The next step would be to take it to an engineer to have the tube drilled out.
But I don’t have the time or patience for that. I wanted to ride it now!
I kinda figured the bottom was sealed, but couldn’t be routed or cut open without compromising the strength? Many seat tubes are “open” at the bottom, so I’m just wondering.
That sounds like a lot of work to save $200. But I probably would have if the frame had any sentimental value.
I just wanted to get on the road, so bought another frame instead.
Thanks Ken, I think that even with my ‘fangs’ mod, I’m still not far enough out most of the time. With my mod, I can get low enough but arms want to extend themselves and they tend to cramp up if the are bent like that for any sort of distance. I want to be 10-15cm farther out and I am small (with small arm length). I would have to disagree with Tony too, I feel like I have more torque, not less with my mod. In my opinion, my best handle would be like mine, with a 10cm extension that can be removed easily. My handlebars are quite comfy for cruising, but as soon as I start to go above 20kph I want to get farther out. The extension would be for racing and faster training rides, but I would remove it for touring, fun rides, etc. Is hitting the square frame really an issues for us vertically challenged people?
Hi Scott,
All I’m advocating is a bike like position, which means arms slightly bent when your body is at about 40-45degrees. If the bar is too upright, your elbows are very bent and hands up against your chest, which doesn’t give you any leverage at all. A bit like riding the Graeme Obree time trial position…if you see T7 riders going fast, they look like that. I think the bar should be at the same level or slightly lower than the seat when riding…same as a bike.
No, the square frame is pretty good as far as square frames go. I only brushed it a couple of times, so probably not an issue.
Thanks for the write-up! Returning after a long absence from the forums, it was good to see a discussion of awesome distance unicycles right on the front page 