165mm cranks

I’ve seen many threads coming along for crank sizes and it is most of the time about shorter cranks. So far 150mm works best for me. I’ve decided to get more experience with my 36" again and I made quite some progress. However I was half wondering if 165mm cranks would make it easier to mount, since they are slightly lower to the ground. On the other hand you have to reach further with your other foot.
I don’t have a brake on my 36" Nightrider Pro and found that slowing down requires a bit more strength in my legs than on the 32". Longer cranks might make that easier as well.
The reason I haven’t bought them already was because I made better progress than expected. Nevertheless I keep wondering about it.

Based on my tests today with my 27.5" uni and 127mm and 150mm cranks, I found the 127mm cranks to be more crotch-friendly. The distance the legs need to travel up and down as the cranks turn is reduced with shorter cranks, meaning there’s less rub on the inner thighs etc.

On rough terrain, the longer cranks gave me more control.

Shorter cranks can too be easy to mount. What I found with shorter cranks is that the wheel doesn’t spin back so quickly as I step on the pedal, due to the reduced leverage, but it’s harder to get moving. Longer cranks, are the opposite. At the moment I prefer the longer cranks for mounting but I think with a little practise the short cranks can be just as easy to mount.

On a bike I would start off on a low gear, and then shift to a higher gear as I gain momentum. On a uni we don’t have gears so we have to think what we are going to be doing most of the time and then configure our machines accordingly. IMO mounting is not as important as the rest of the ride.

As with the geared hub, the next step would be to engineer cranks that you can extend and retract during the ride. :smiley:

Don’t do it!
Get a stair climber instead. It feels roughly the same.

Once your skills catch up they will be never be used again.
Keep your 150’s on and ride it.

Put your other unis away and bring your 36 skills up.

TBH the main issue with unicycles is lack of a proper gearing system. Trying to compensate for lack of gears with different wheel sizes is far from ideal.

A larger wheel reduces roll resistance, but requires more energy to spin up. I think 26-27.5" wheels hit a sweet spot for the average sized adult human. Once the ideal wheel size has been established, any other wheel size is going to deliver an inferior riding experience. For a given rider, wheel size should be a fixed parameter. Likewise, crank length should be chosen in relation to the rider’s leg length. If more torque is required, this should be achieved using gears not different crank lengths.

At the moment all we have is the Schlumpf 2-gear hub. If someone comes up with a 5- or 6-gear hub, that would really take unicycling to the next level.

Don’t bother. They won’t be substantially easier for anything, and you’ll wind up hating them in short order. If you can’t cope with a 36er with 150s, ride a 29er with 137s or shorter. Mounting will be a piece of cake, you’ll be just as fast, and you’ll have a couple pounds less rotating weight.

Some people ride serious muni on a 36 with 170s. For years I found 150 was my ideal compromise for road and trail. The last few rides I’ve done on 125s. I am not a short crank fanatic (any more!:o) but I do not recommend buying longer cranks to make riding or mounting easier. I did that many years ago (170s on a 26) and riding it was no fun. Seriously, the mounting will get easier with practice. Indeed, the more you ride, the more confident you will become in those first few seconds after a mount. Compared to 150s, 165s will put your seat 15 mm closer to the ground, which is negligible, but they will make riding on the flat so much slower and less fun.

Stick with the cranks you have and practise a little each day.

If you are the tinkering type I would buy an inexpensive set of 165mm cranks and see what you think. It’s about the only way to get over your curiosity. :stuck_out_tongue:

Personally I never liked the size. I’m OK with them now but in the earlier days for some reason I never found anything over 160mm comfortable, as I’ve progressed as a rider I became comfortable with a wider range of crank sizes but found less need to go with the longer sizes. I don’t often go over 150mm anymore.

Most road bikes have cranks between about 165 and 175 mm. 170 is more or less the standard.

That’s fine when you’re pushing a gear that gives you the equivalent of an 80 or 90 inch wheel (or more) but when you have only the resistance of a 36 inch unicycle, it’s like trying to go everywhere as fast as possible in bottom gear on a road bike: horrible.

With slightly shorter cranks, a unicycle wheel is slightly less responsive to small changes of input. I find that makes it easier to use the back pedal as a step when static mounting my 36. It also means that when cruising, I feel that I’m pushing against something rather than spinning out and bobbing up and down on the saddle.

Ok thanks for your input. I will stick to my 150mms and suppress my curiosity and use the money on something else. Next time I will try one more time on the parking lot and then take it to the forest nearby where they have many kilometres of bycicle lane.

Hi there

When I first bought my 36 I rode it with the KH dual holes cranks (137/165mm) for quite a while. The 165mm lenght was quite handy for idling, hopping and riding up steep hills. Where I live is very hilly so I found the 167mm really handy!. I would ride up and down the steep hills on the 165mm lenght and change it to 137mm when reaching the flat area of town (promenade, etc…). Nowadays that I’ve got better at riding the 36 I’ve moved on to the 150/127/100mm multihole combo (the 150mm hole is handy to have when tackling offroad sections or extremely steep hills). I mainly use the 127mm.

If you live in a flat area I think 150mm should give you plenty of leverage to improve the mounting, riding etc… As other peole have said it just a matter of riding the 36 as much as you can… You will quickly get used to mounting it, riding with shorter cranks etc…


I just bought a set of dual hole KH 165/137mm Spirit cranks for my 29er which had 137mm Moments on it when I bought it. This was primarily because where I usually practice is a bit rough and hilly. My 24er has 150mm cranks and it felt fine so I thought I’d try the 165s on the 29er. Anyhow, I swapped the pedals to the 137mm holes this evening since I couldn’t get used to the 165mm ones.

I have 150/125/100mm VCX+ cranks on my 32er – to be honest I haven’t experimented with the length on those but the 165/137 might find there way onto it to see how they feel, but my first impression is that the 165mm ones are too long, maybe even for the 32er.

I know this isn’t for a 36" but I was surprised the difference in feel it made.


I don’t know if this is relevant for switching crank sizes with a 36", but when I first got my nimbus 26" municycle last year it came with 150 mm cranks. This was my first ever mountain unicycle; I already had a 24" freestyle and 29" road unicycle(I would occasionally ride the 29" on rocky trails).

I took the 26" on a few trail rides and struggled with some rocky uphills. So I decided to switch to 165 mm cranks to see if this would make a difference. It felt really awkward at first, even free-mounting it was more difficult, but I soon got used to the 165 mm cranks and I was able to successfully climb those rocky uphills I previously struggled with. The biggest issues are the wheel is more wobbly and it’s very slow.

Lately I’ve been thinking of going back to the 150 mm cranks because I think I’ve gotten used to the wheel size enough that I’ll probably be able to do the rocky uphills with them as well as I do with the 165 mm.

As an aside, over the past few months I kept switching the cranks on my 29" from 114 mm to 150 mm then back to 114 mm and on and on recently. I swear this helped tremendously with improving my idling with this wheel size, even doing it pretty well on the 114 mm cranks after having mastered it with the 150mm cranks. And I rarely practice idling with the 29" — 95% of the time I practice idling is with my 24" with 125 mm cranks.

I have used mostly 165mm and 170mm cranks on my 26" muni. I spent some time using 150mm cranks. They were great, except for the very steep hills in my neighborhood. I could make it up most of those hills, but I was putting a lot more stress on my hips/knees/ankles. I am 6’2" and 210 lbs. I think that factors into using longer cranks. My cadence is not great with long cranks, but it has improved since I started riding with two hands on the bar ends. When I ride my muni after previously practicing on my trials uni (with shorter cranks), the long cranks initially do not feel good. However, I adapt to them, partly by getting my hips to fall more during each pedal stroke. In general, I am able to ride longer distances (muni/XC) without burning out on longer cranks. If you are accustomed to shorter cranks, then you try longer ones, you are probably not going to like them. I’ve read accounts of this happening to multiple riders on the forum. As with anything else, you have to experiment with something new for more time, allowing yourself to adapt to it, before you can really judge it.

My understanding of crank length is: Longer cranks give you more power in the 3:00/9:00 position, but the power is diminished in the 6:00/12:00 position. The opposite is true, relatively speaking, of shorter cranks. I sometimes feel like I’m slogging on longer cranks and spinning on shorter cranks. With practice, however, I can spin and pedal though the 6/12 “dead” position with greater power–on longer cranks. With shorter cranks, however, my main limitation seems to be my strength (or lack of).

I don’t think stepping one “cranksize” (step smaller than 15mm) down creates an issue that could not be solved by a reasonable amount of practice, unless you are frequently riding hills that are right at the limit of what’s possible. Likewise, stepping a cranksize up will not help you much more than a reasonable amount of practice will.

One learns so quick, that I don’t put much weight on most peoples stories of succes after changing equipment. No offense intended to anyone, but I’ve experienced so many occasions where something that is hard the first time becomes easy the second time, without setup changes. One tends to remember the times where the setup was changed more often though.

Setonix, don’t you have 165mm cranks on the Hatchet? I remember reading that you found the Hatchet to “eats energy”, the 165mm might be better and you could try them on the 36er.
I just did a search about the Hatchet and came across some posts you made, I’m thinking about getting one for winter snow.

Hi Chiliagon, my hatchet has 150mm cranks. It is a 26" uni and I don’t see any added value in riding it with 165mm cranks. I’ve so far only experimented with riding shorter cranks and even though 140mms are comfy on flat, I find them a pain when having to climb. I tried those on the 29" and 32" unis.
I ride the Hatchet not so often, but occasionally just because it looks cool. I’m not sure if it is the seat or the wide wheel, but I end up sitting half on the seat, like when riding with road camber. Haven’t tried with another seat yet.

Most bikes have cranks around 170 mm. The wheels are around 27 – 28 inches. Bottom gear on a road bike may be something like a 1:1.5 ratio, meaning that in bottom gear you are driving the equivalent of a wheel of around 43 inches. (Much lower on a mountain bike, somewhat higher on a bike designed for time trials.)

Point is that a 26 inch wheel is equivalent to a very low bottom gear on a road bike — in fact, a gear where the rear cog is slightly bigger than the front cog.

Therefore it should not be difficult to get a unicycle up any hill that you could ride a bike up. The uni may be slightly less efficient (more tiring) but in simple terms of power to weight ratio, you should be able to take a 26 inch uni up anything that you can ride a road bike up. (I’m not counting the sort of short steep hill that you can get up on a bike with momentum but would struggle to pedal up.)

For comparison, our biggest and longest 2 local hills are a challenge on either of my bikes (a so-called “gravel bike” and a fixie), but I have ridden up them on my 36 with 150mm cranks.

The answer to riding a unicycle uphill is a lot to do with practice, technique, and stamina, and little to do with longer cranks. Indeed, within certain common sense limits, short cranks can be easier. If you think of being on a stepping machine at the gym, longer cranks mean you are going up taller steps. There’s less resistance, but it’s a bigger, clumsier movement.

I have always found that the place longer cranks really come into their own is not going up the hill, but coming back down. I don’t use a brake, and it is very dangerous to let a big-wheeled uni run away with you on a descent.

When you are learning usually the next ride is better then the previous, but a change in setup can still affect your riding. For a learner it can speed up the learning process. For example, after switching from the regular Velo saddle that came with my first uni to a KH Fusion One, my riding suddenly felt a lot more comfortable, which in turn boosted my confidence and my ability to make progress. I’ve tried the old saddle again out of curiosity and it does hinder my riding.

Another example, the grips on my trials bike. Everybody recommends using grips as thin as possible, but I have long fingers and would get very painful hand flappers if I rode for more than an hour. I used these grips for years and never knew better. After switching to thicker grips, contrary to everyone’s advice, the flappers stopped. Now I can ride until I’m exhausted, and my hands don’t hurt at all.

Today was the 3rd Satuday in a row since I decided to be able to ride my 36" again. During the week I have to spend time with my kid after work and when we then do ride, I ride a 26" as I can go slow enough, when my daughter goes slow, and fast enough, when she decides she has too much energy.
First I went to my newly found old parking lot to see if I can mount the uni easy enough and after 3 mounts, decided to go to the forest where I rode 20.15km. I only had to mount two times, and decided it was better to keep riding than to take a break. Riding the 36" is actually very comfortable and I felt with some training I should be able to get a good speed out of it. I did between 17-18 kph.
It takes about 1-5 tries for me to mount, so I don’t see the need to buy longer cranks anymore, also riding uphill was well doable. The only thing I forgot to put on my uni were handle bars, which make riding much more comfy.