First time trying 150mm on the 24" instead of 125mm

First time changing cranks, too. I changed the following:

24", 125mm->150mm
27.5", 150mm->170mm

Didn’t get to try the 27.5" yet, but the 24" shift was pretty trippy. You all know the pros and cons, but here are mine:

  • Even easier to freemount
  • Easier to crush things and go up hills/control
  • Going backwards was easier

= Slower

  • I feel like the range of height my foot goes through is uncomfortable (too high at 12 o’clock, and too low at 6)

What is everyones preference? Does anyone prefer 150mm on the 24"?

It depends on what I am using my 24” for.

My Schwinn retro 24” has 150mm cranks and is what I ultimately learned on. As a result, I still have my 27.5+ Oracle set up with 150mm cranks.

My Koxx White Russian 24” is now set up as a road uni with a CST Cyclops tire which will be replaced by a Maxxis Hookworm when the Cyclops wears out. That uni has 130mm Impact Groovy cranks, which I totally love. It seems like the perfect crank length for me, for that unicycle.

Then, there is my Koxx Track Monster 24” Muni. That one has a 24x3 Halo Contra (Duro Razorback) tire and 160mm cranks. 160mm cranks definitely feel too long for a long-distance road ride, but they seem perfect for off-road use and traversing obstacles (roots, rocks, etc.), and rides in which I might come out of the saddle every now and then.

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Woah nice spread, and thanks for the details. Good to know. I am gonna give it a few days of riding to ultimately make a decision on keeping 150 or going back to 125.

125mm is the one length to rule them all!


Ryan, I forgot to add that the guys I ride with use 125mm cranks on their 24”. They feel the same way @lightbulbjim does.


I should probably add some nuance to my somewhat glib answer. Of course, use whichever cranks you like. Some lengths certainly work better in some scenarios than others. But if I could only have one length on all of my unis, it would be 125mm.


125mm is my most popular length for 24" & 36"/Geared. My 29" is currently on 150mm but has 127mm holes too which make it quite fast to ride around.

150mm on a 24" would be too long for me, I’d probably be striking the concrete with them.


As I said on another thread, the 150s are great for learning on and for getting confident, but shorter cranks will ultimately deliver a faster and smoother ride.
Personally I use 125s on my 36er and 26er but I’m desperately seeking some 110/127 KH Spirit Cranks for the 26er.

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Yep, well said. My munis have 137mm cranks (24" and 27.5"), I don’t like 150mm for the same reasons.

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Hey thanks everyone for the notes.

Although it feels awkward on the first ride, I think I am going to keep them on for one week (I ride daily). Then if I still feel the same way, I’ll change them out.


150!? What world are you living in? My 24 has 89s! :laughing:

[Ok, yes my usage for it (right now) is for commuting and stuff like that†. No off road at the moment, so this is not a proper comparison but… you know… I have to make the joke. :wink:]

† Since you follow me on Strava, rides like this:

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More seriously though, when I do get off road I typically use 115mm or maybe 125 if I wanted “long” cranks on a 24.

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Wow! My eyes have been opened. Very often, I am amazed by the things other members do on a regular basis, that I would have never tried on my own. And, I thought my 130mm cranks felt fast!

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24x3 and 150mm cranks is the best combination I have found so far for muni. Shorter cranks simply can’t climb as well and longer cranks just seem to be slower without any climbing advantage on a 24". On my 36er or my Hatchet with the 4.8" tire 170s seem to work well though.

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For MUni on my 24, 150s are the best length, for negotiating rough, rocky terrain, and provides optimum leverage and torque. 137s would be fine for more XC stuff. I remember when I first started riding MUni in 2006, everybody was using 165s, and these were some of the top riders of the time.


So I’ll put the disclaimer that my riding is usually 100mm cranks on both my 29" with 114/125 for Canadian winters and 150 for muni. I’m currently rocking 90mm cranks on my 24" for speed and I find the size very capable. It feels like the equivalent of a 125 on my 29" in terms of effort needed for climbing and worked for riding around in my city during winter when there was a bit of snow and uneven ice.

I’ve paired it with a 2.8" tire with some tread and it’s been a pretty fun uni to ride around on.

@RyanDorkoski my experience was similar to your when starting out and I find there is a bit of a few minutes of learning if I switch from the 100/90 to 125 or 150 as I kinda need to get into the groove of a good cadence again. When I was new it felt like a night and day difference but you will adapt.

If you are looking to increase speed, best recommendation is to spend time learning to spin your longer cranks (125 in my case) really good and that cadence will carry down to smaller cranks.

I currently average about 12-14kmh on my 24", I was toying around with getting some 75mm cranks but the 100s on my 29" are the point where I feel I would lose a lot of control on something smaller and the 90s ride really well on the 24" and make climbing a breeze while still going a decent speed.

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On my noname 24" I think I might have 125’s installed and the wheel is squirrelly so I think i’d be better off with a shorter length on it.

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Thats very helpful. Thank you.

Thanks everyone. I’m enjoying all the responses :slight_smile:

I tried 75mm on a 24” and 26”, it was fast and slowing down was hard, might be more doable with a brake though, but I don’t have one. 75mm feels pretty natural on a 20” but only if you’re trying to go fast, not good for tricks. I’ve since put 125mm back on all the unis.