best cranks for 26" Nimbus road

I bought a new Nimbus II 26" for riding around campus and getting some exercise.

Starting back riding after a 30 year break. So, I’m still “new” - can ride just over .5 mile before I get sore / tired and have to take a break.

I’m using the 150 cranks that came with it. I don’t seem to be going very fast. I had a hard time passing some people who were walking (ha ha).

Since the 150 cranks were “beginner / learning again” cranks - should I consider getting something shorter now (have only been riding 2 months).

I’m thinking of getting the KH ISIS Spirit DH Cranks 110/127mm ?? but, might not have that much money to spend on it right now…so, I’ll be checking the trade forum…

thoughts? comments?

I have a Nimbus 26" inch muni, (the Oracle), and I use KH Spirit 127/150’s. I originally got it with the Nimbus Venture 165’s, but those were way too big for me. 150 is a nice sweet spot - plenty of torque, but you can also get speed if you want. Are the commutes you plan on making with it relatively flat? If so, 110/127’s might be alright.

Also, do you have a brake? If not, you might want to go with 127/150’s to get the extra power when going downhills.

EDIT: Just looked up the Nimbus II on UDC and saw that it didn’t have brakes…you’d think I would have figured that out seeing as I have the 20" version. :roll_eyes: That being said, I would definitely recommend 127/150’s. You can keep it on the 127 hole for when you’re on flat terrain and switch it up to 150 just in case.

I know you are just getting back into it, so I understand wanting to start with longer cranks. I can’t imagine riding a 26" road uni with anything longer than 125 (127 is the same thing in practical terms). In fact I would bet that before long you would find yourself riding on the 110mm position most, if not all, of the time.

If I was looking for the ideal crank for a road uni, and I didn’t need to mount a disc rotor to it, I would go for something with no offset, and light like Qu-Ax lightweight ISIS cranks, or Ventures. If I had only one set of cranks I would go with 120-125mm for the extra leverage and still fast spinning.

Offset makes the Q-factor (width between pedals) wider. It can be really helpful with long cranks to prevent hitting your ankle against the crank. Short cranks don’t suffer that problem (unless you have very small feet). So, running straight cranks with no offset moves your feet a little closer together making it a little easier to spin the cranks faster.

Light cranks because on a road uni you don’t need the extra strength, or the associated extra weight. The Qu-Ax cranks used to be pretty cheap as well, but at the moment I don’t know where you can find them under $50. It used to be cheaper to get two pairs of them than to get dual hole cranks! You may still be able to find them if you search around a bit.

Maybe put a wanted thread in the trading post and see what shakes out. Also, you can try calling UDC to see if they have any old stock that’s not showing up on the website. I’ve gotten lucky a couple of times.

my riding is mostly on level ground - maybe slight uphill or downhill (think sidewalks in a park) - nothing off-road or extreme.

I will also be keeping my 150’s anyway… so, I always have those to use if I do switch to riding up/down hills.

As jtrops has said, its pretty hard making a road uni work with 150mm cranks.

The QU-Ax lightweight cranks are cheap and perfectly strong enough for most riding styles. 125/7 is probably a good intermediate crank length while 114 is something to work up to.

To get them cheap, it may be worth sending an email to as they cost £14 ($21.50) per pair with VAT (20% tax that you don’t have to pay). It is possible that you may be able to get 2 pairs for about $50 including shipping.

EDIT: still has 125mm in stock for $24…

okay - silly question - what is and

I ask because redirects me to a site selling arcade machines and is blocked here at work as malware…

are you really meaning ?

also, one more question… I bought the nimbus II because I wanted something that could handle my weight (220lb) without fear of breaking it… I think the most I would ever do is go off a curb… will the Qu-Ax Lightweight be okay for that?

They shouldn’t care at all and in fact are fine for basic off road.

As long as you aren’t planning to do something out of a trials or crazy muni video they are strong enough.

UDC is secret forum code for There are multiple sites under the umbrella. The US based site is The UK version is
You can switch back and forth by clicking on the flags at the top of each page. Happy shopping!

just bought 125s

I found a website called that sells the Qu-Ax Lightweight 125 and had them in stock. Got those and the extractor tool. Will see how these work out.

thanks - I actually bought my unicycle from them two months ago and was shopping for the cranks there - just couldn’t figure out how they got UDC out of - did a search at google and found unicycle-dot-com = UDC so now it makes sense…

Now that you have two sets of cranks, 150mm and 125mm, you might occasionally swap them.

On your weight alone, I’d suggest the 150s. I assume you’re pretty tall.

Longer or shorter cranks aside, what you’re trying to do is increase your cadence. Sure, it’s easier to do on the shorter cranks, but as you develop more stability while riding, your cadence will increase, even with longer cranks.

You’re probably going to experience a loss of control on the 125mm cranks, which you’ll regain with practice. Does the across-campus ride involve swerving to miss pedestrians? If so, you might notice that the shorter cranks cause the unicycle to resist changing direction and speed. How significant this change is…is up to you to decide.

If your knees start hurting with the 125mm cranks, I suggest going back, for the time being, to the 150mm.

Finally, if you trying to learn a new free-mount, I’d recommend doing it on the longer cranks.

Happy riding!

I can agree with the Happy Riding sentiment at the bottom but otherwise this just leaves me wondering.

Switching cranks can lead to a sense of less control any way you switch. 125’s on a lightweight road 26 are not short. I’m not sure why 125’s would give anyone knee problems on a 26, but I do wonder why you say they might.

The OP is a returning unicyclist, not a complete newb.

To OP:
I hope you enjoy the Qu-Ax cranks. I really like them for what they are.

Just thought I throw in my $.02. I have several unicycle sizes, with numerous crank lengths. I had a friend here at work a while back who was jogging before work, and I thought it would be fun to ride along. With some experimenting, I found the 26" with 125 cranks was a good pretty match. He’d run away from me on downhills, but I’d catch up again on uphills. On the flats we were pretty even. (YMMV)

that is good to know - jogging speed is about all I want right now - not interested in speeds approaching uncomfortable spills.

jtrops: the last thing I should do is discourage, insult or condescend to another rider on the forum. My comments were only relative to my personal experience with crank length, and to a lesser extent, based on forum posts from other riders. I intended to point out relative differences between crank lengths, not to say that one was better than another (though I know what I like, and my riding conditions are particular to me, which gives me a certain perspective).

By ‘control’, I mean ‘leverage’ or ‘torque’. As I decrease the crank length, I have less leverage. A great amount of leverage or torque is not really necessary for road riding, which is generally smooth and straight. So, I’m not disagreeing that 125mm or shorter is the way to go.

You were wondering why I would say 125mm cranks might cause knee problems: When we fall forward, we have to pedal forward to compensate. When we fall backwards, we have to hold back with the knees to stay upright. As we improve our balance, we respond more quickly to back and forward balance issues. Beginners, I assume, will benefit from longer cranks; they need the added leverage, because they are less balanced; they are falling forward and backward to a greater extent and need greater torque to overcome this imbalance. Making these adjustments with shorter cranks implies having to use a greater force, which could put more pressure on the knees. Add to that, the OP stated his weight was 220 lbs. I tend to like longer cranks, and I am on the taller/heavier side, for unicyclists. I wonder if the same might be true for the OP. I have never had knee problems on the unicycle, luckily, but I have felt more strain on the knees after riding with shorter cranks. I have read several posts by riders who started with longer cranks, went shorter, had knee pain, then lengthened their cranks again. I think those posts were mostly related to mUni. Perhaps some people have knee issues already, issues which might be exacerbated by putting extra force on the pedals.

The OP didn’t specify why they were out of breath after .5 miles. It sounds like “beginner’s inefficiency”. I don’t mention this to insult the rider, but just to point out that any new technique (including returning to unicycling after a hiatus) is generally accomplished with greater physical effort. One reason for being tired-out after a few minutes: the “fast-twitch” muscles may be spent. These are the muscle fibers associated with heavy loads, and whose power is not so easily regenerated. Assuming the leg muscles are the ones being tired out, I wonder if shortening the cranks would make matters worse. There is only one way to find out, which is switching back and forth between cranks, which is what I said in my original reply.

I have a vague recollection of reading some older threads about crank length…which turned into flame wars. I am not experienced enough to speak with any authority about this subject. The purpose of the forum is to get good information on unicycling, so let the best ideas prevail!


Okay, that makes sense. I still think that for a road uni with a 26" wheel there aren’t many situations I could think of that would require the kind of torque 150’s offer.

Thanks for clarifying the knee thing. I too have bad knees, and I have been nursing a knee problem for the last 2 months hoping to get riding again soon. My problem came from road riding up a very steep hill (literally a mountain). When I said road riding I meant bicycle. Weirdly, unicycling hasn’t ever really given me knee trouble. Still I understand where you are coming from.

When I was a beginner I built up a 26, and even with 125’s I felt like it was too much leverage for the uni, so I rebuilt the wheel as a 29, and it felt like a good match. That’s why I consider 125’s the longest I would recommend for a uni like this one regardless of how long the rider has been at it. I guess the fact that the question is here in the first place is somewhat telling of general uni knowledge, but maybe not experience.

As you indicated before, since the OP has the 150s, and the tools to swap them there’s no harm in keeping the options open!

elpuebloUNIdo - I take no insult. I did .67 mile last night and would better describe it as my thighs giving out rather than my breath. It just gets to a point where I’m feeling pretty sore. I know this will get better with time. In the beginning it was my quads. Those don’t bother me now - seems the struggle has moved to my inner thigh. I thought by moving to a shorter crank I would go the same distance with less movement which would mean less strain on leg muscles - however, as you point out that may not be the case. I was not willing to spend $120 on cranks to find out - however, after finding the aluminum set for $25 I think it is worth testing.

When I purchased from UDC I asked for their recommendation on cranks and they said the 150 was standard and would be good for me since I was re-learning after 30 years off. I think they were correct. The 150s have done well. As a beginner a small pebble can upset your balance. It is nice to have the torque of the 150s to help with catching my balance. I shall see how the 125s do… but, will keep my 150s on hand in case I need them.

138s worked for me.

I bought that same unicycle last year, as I was returning to riding after many years. I ordered mine with the Venture II 138mm cranks. It was an ideal set up and after almost a year I find that my strength has increased enough to use the 138s on my freshly built 32", and I bought Qu-ax 125s for the 26". I ride mostly paved bike trails with mild variations in grade and altitude.


yea!, i just installed 138s in my "26 oracle, it now rides faster but still have good torque, well, i’m used to my “36 with 125s, so my 26” is always easier to handle.

it came originally with 165s and that was the way i learned unicycling but now i feel that configuration is like going in first gear in a car , i mean low speed.