Hello,
Have a 26" nimbus with kh moment 137mm cranks. I ride mostly street now, and it doesn’t provide enough top end. I was thinking about swapping to nimbus venture 79-100mm cranks… would this work?
Also are the older kh moments more wide/narrow than a venture crank? Curious, because they are a older, and heavy design.
Only if you pedal faster. Shorter cranks don’t necessarily make you go faster. They just make it more comfortable to go fast.
Moments are wider than Ventures.
what is your end goal? I ask because I’m dealing with the same thing on my 29er and I have to keep telling myself “it’s a unicycle, not a bike!” It’s never going to be fast, just enjoy being out riding.
I’m running 125’s and probably will go down to 114’s (or whatever the smaller size is on my dual hole kh moments), I started with 137’s and there was some improvement when I went down to 125, it felt better and I can spin faster but I have to work at it. Switching to shorter cranks is not an automatic speed increase, you still need to learn to spin faster. I’ve observed that I don’t really like to spin fast, so I’ll never be faster.
What @lightbulbjim said is right, the moments are wider. I like the width much better, It makes a surprising difference, but I’m a big guy. I think the weight is worth it, I also like the chunkier look of the moments.
Shorter cranks may or may not increase your top speed, but you will be more comfortable riding at those speeds once you become comfortable with the new crank size. This might take longer than you expect (don’t expect to be faster the first time you use shorter cranks)
KH Moments have 10mm of outward flair or “q-factor”, Spirits have 12mm of q-factor while the Nimbus Venture II cranks are zero q. Venture cranks will put the pedals 10mm closer to the center line of the wheel on each side.
It’s too bad experimenting with crank length can be so expensive but I had good results commuting a 26" unicycle with 100mm cranks for a while. I did not try shorter but 89mm might have also been a great size. If you haven’t ridden short cranks before I would not go much (any) shorter than 100mm if you want to maintain control and maneuverability in an urban environment. If you don’t have to deal with pedestrians and traffic or any kind of hill then I might consider shorter.
Good luck!
I’ll ask about this rather than suggest because I don’t know for sure, but I’ve been planning to add handlebars to my 700c/29" road uni, in order to be smoother and more under control at higher cadences. The bars seem to do that on my 36" but I haven’t gotten around to deciding which ones to put on the smaller one yet. Think they’d help?
Since I’m experimenting with a dual position handlebar on my G29 (still modifying it but this is one of the latest version of it) I can say that I notice the differences between holding : no handlebars - moderately long and long handlebar.
Basically the longer the handlebar is, the easier it becomes to pedal fast / to climb hills, the angle also counts, experimenting is finding the sweet spot where the handlebar brings both ability to accelerate/pedal fast and ability to control when you have to deal with some muni-like conditions.
Comfort is also a factor to take in account if you choose the very long handlebar option and want to find the sweet spot:
-Too much under the seat height and you have to deal with lower back pain, because your body is a bit bent, and uneven floor is harder to manage but you have a more aerodynamic position.
-Too much above the seat height and you loose the lever that makes the pedaling easier and it becomes a bit tricky to hold the handle with both hands in some situations, but the comfort on the uni is very good, no back pain.
Note : I hold my handlebars with both hands nearly 100% of the time.
The fact of having two positions handlebar (people will become sick of reading me repeating this 
) also brings the option of changing my position at any moment of my ride, which is a great plus in term of comfort.
About the pedals length, it’s a question of dilemma.
the shorter the cranks are, the easier it is to keep a high cruising speed, but you loose control and comfort at very low speed/free mounting/ uneven terrain.
Long cranks are safer for the knees since the lever reduces the forces needed to accelerate, you have more control at low speed or at moderate speed on uneven floors, but keeping a high cadence is more tiring since the legs are moving around a bigger circle.
I don’t think so. You may ride on the street, but as far as I can gather, you don’t ride street, there is a big difference.
Street unicycling:
Riding on the street:
Sorry, that stuff bothers me a lot.
I’ve been riding on 110mm cranks and saw some increase in speed but not much. I saw a bigger increase in speed when I built a new wheel with a lighter hub, tire and rim. I also removed my brake.
Big wheel = easy speed
Shorter cranks = less easy speed
Geared = not easy at all speed
If you want raw, consistent speed, I would consider a larger wheel and keep the 26 on the trails.
Funny how everyone else here knew exactly what he was talking about, then you have to pick on him about this? You need to learn to hold your tongue.
Sorry, but the senseless bagging on someone for their use of english bothers me a lot.
It’s not about the use of english, it’s the point that those are very different disciplines, and while in this case there is enough context to understand it is a mistake, I felt OP might not know the difference. I might have sounded a little rough, but I have come across the issue where people introduce themselves with: “I do street unicycling.” on this forum, when they mean “I ride on the street” or ask for a good “street unicycle” and after 5 people suggest different 19" unis, it turns out they are really looking for a 29" commuter. So no I don’t think correcting that mistake was senseless.
Anyway, to get to the real point of the post: a 26" will not be a really good long distance uni, if that’s what you are looking for, but if you want to upgrade it’s speed on the cheap, something like 100mm -110mm cranks are the way to go. Even 125mm will make big difference. I would only go below 100mm on a 26" if you have any sort of traffic/curbs on your rides, or you are very experienced, since it makes braking, accelerating and turning pretty difficult. And, like others pointed out, with shorter cranks you will get the possibility to go faster, but it doesn’t immediately make you faster.
Thanks for the comments! Yes, getting the hands out in front and pretty low makes a nice triangle with the seat and pedal contact points and seems the most stable. I like how the bars are set on the Coker that I got from LanceB, approximately level with the seat, but then I’m accustomed to a low posture from skating and from having a high-saddle/low-bars setup on bicycles. It feels more powerful to me and I can deal with the kind of lower back pain that comes from muscles needing to be trained. The shooting-down-the-leg nerve pain comes more often from being too upright with my lower back compressed and worries me more.
Neat! What did you go with? Pictures?
Unicon 18
Here’s a video from Unicon 18. It’s me on my 29er in the 10k.
Ok, so I’m not the fastest or most skilled rider but I try my best. It was wet that day which made the race a bit slower than anticipated. Only a few weeks earlier I had a face plant while riding at about 10mph on the new wheel build … and didn’t want to repeat that incident.
The wheel has a Velocity Dyad rim, KH Spirit hub and Marathon Supreme tire on a Oracle frame.
It depends. An extension handlebar gives you more leverage which I find important for large heavy unicycles (eg Schlumpf 36)
When pedaling very very fast at low resistance, I’m marginally quicker without the handlebar- I like to have the hands close to the seat as it gives me more control and less wobble.
I raced 700c/75mm cranks at the last 2 Unicons without a handlebar (came 2nd at Unicon 17 and 3rd at Unicon 18). On the other hand, the rider/s ahead of me had extension bars, so it comes down to personal preference and experimentation.
For long distance comfort, the bar is useful to give more hand positions, so I do use it for longer rides.
Cranks are cheap relative to geared hubs (or a different wheel size), and as long as one sticks with a single standard (eg ISIS), they are a good long term investment for any unicyclist.
My commuter unicycle for many years was a 29"/100mm unicycle, which was good for getting/holding groceries as well as getting me around town relatively quickly.
Optimal crank length does come down to experimentation- a heavy 26 or 29 with Muni tyres wouldn’t necessarily be fast with 89mm cranks, but a lightweight 700c has plenty of speed and power with 75mm cranks.
I just did Lake Taupo Cycle Challenge on a 29"/75mm, and there were plenty of hills (1600m climbing), but was an hour slower than when I did it previously on 700c/89mm.
This gives you an idea of speeds and crank length (or at least what different riders use), in relation to a 700c or 29" wheel size (note tyre choices vary, the correction notation should be 622 ISO rim size):
Standard Marathon Unicon 18
I never really thought about wheel weight when thinking about speed on my 29. So as you shorten your crank length, you should try and lighten up your wheel (if possible)?
One thing mentioned by Ken could also help. Find a good tire for riding on streets.
If you have narrow rim you could try puttin one of this road-bike-style tires in 26" size like https://www.schwalbe.com/en/road-reader/durano-dd.html
For wider rim you should find something wider, which will give more resistance, but also more cushion and might be better for you in the long run.
The classic is Big Apple coming in three widths @26": https://www.schwalbe.com/en/tour-reader/big-apple.html
but there are many other options from this and other brands.
If you want to go offroad from time to time find a XC tire for fast races. This gives still easy rolling but some more grip offroad.
The difference in speed between heavy DH tire and touring tire is enormous.
You’re movin’! 
From the way you had your arms, as though you’re poised to catch yourself at any moment, it looks like the incident might have still been on your mind. And I don’t blame you.
For me at least, there’s a feeling at higher speeds that if my balance gets a little bit forward, I might not be able to pedal any faster and catch the wheel back up to me. And then, if I couldn’t keep up and had to step off, I might have to suddenly start running really fast. It might get better with practice at high rpms. That’s another thing I should probably work at.
All great stuff. Enjoy!
It’s a neat wheel (sorry for hi-jacking this thread!), what width is the tire?
I’m shopping for a future 29" build for a Schlumpf hub. I’m more inclined to make that a road uni, therefore with a narrower rim than the stock KH taking narrower tires like a Big Apple 2.0".
On word of caution about using short cranks is that emergency stops are out. Also riding in the dark across uneven roads may result in a sudden fall. You need to be able to anticipate a little. Usually i take bumps by raising a little from the seat and keeping the wheel going. With longer cranks you can stay in the seat and use the pedals.
