Differences between Cranks?

I’m looking into building a new wheel and I’m confused on the difference between cottered cranks, cotterless cranks, and splined cranks. I’m into street so there’s a little trial but not much. Which kind should I go with? Thanks.

Is there anybody that knows?


order of strenght in best to least: splined, cotterless cottered
order in which made from oldest to newest : cottered, cotterless splined

IMO the best build wheel would be:

KH '07 rim or Koxx1 solid rim (stronger, but heavier)
Titanium spokes $40 vs. $15 for steel.
moment hub, w/ 125’s

How little are you Littleman ?

The main difference is cotterless has a square ended axle, for square holed cranks. These uni’s are light and less expensive. Splined uni’s are for fat guys or people hopping around and off things. They may cost 2 or 4 times $, and are sometimes heavier, but tougher. So how much do you weigh, and are you making a jumping uni ?

If you want a really light street uni (also much less$), just put a 2.25 bmx tire on a freestyle, just make sure it clears the frame and keep it to flatland only or you will be replacing hubs and cranks regularly.

By his post, I would say yes.

It is sometimes useful to remember that everything was the latest idea once. People rode the Tour de France on cottered cranks, and later on cotterless cranks. They are good enough for riding up an Alpine pass as hard as it is humanly possible to pedal.

My first uni had cottered cranks and was never a problem despite the fact that I rode it on rough tracks and down kerbs.

However, there is no doubt that cotterless cranks are neater, stronger, more secure, and generally better all round than cottered cranks.

The question then is whether it is worth the extra cost and weight of going for splined cranks. Splined cranks are simply a more sophisticated form of cotterless cranks.

If you are very heavy and/or you are going to place sudden huge loads on the cranks (e.g. lots of hopping and dropping) then splined cranks will stand up to this better.

Otherwise, cotterless are perfectly good, even for quite tough riding. Only one of my unicycles has a splined hub, yet I have ridden all of my unicycles off road and on steep hills, had lots of UPDs, and never damaged either a hub or a crank.

Why 125s? I ride street and trials and ride with 137s. I can crankflip, hick, 180flip and clear big sets fine and then when it comes to trials you have greater controll with the extra length.

Flatland is lame and boring to watch, maybe you dont break things as much and you probly wont hurt your self as much/bad but it suks :smiley: You should buy the Kh moment hub, you will save money in the long run and it will give you confedence in doing drops and stuff. Then get it with 125s or 137s (If you know your going to be doing trials get 137s)

Dont buy cottered or cotterless if you know you are going to be doing drops, cotterless hubs seem to break realy easy which isnt nice and is realy anoying or you end up bending there cranks. The KH moment hub isnt that much more exspensive than like the cotterles UDC cromo hub (suposidly the strongest cotterless hub) I think the cotterless hub is about £30 and the monent hub is about £45 when you think how much more the moment hub will take, its a bargin :slight_smile:

the hubs arent much more, but the cranks are. :slight_smile:

so true

With the combination of the qu-ax isis freestyle cranks, the moment or qu-ax ISIS splined hubs, there’s no point in going cotterless any more, unless you want a crank size that isn’t available in isis, ie. shorter than 100mm.

The qu-ax freestyle isis cranks only cost £12, and they are surely as strong as most cotterless cranks. If you break these cranks, it’s a pretty good sign you need a full on splined setup. At that point it’s only £40 to upgrade to KH moment cranks, rather than having to spend £100 on rebuilding the wheel with a new hub + cranks.


So from your replies I’m pretty sure I shouldnt go with cottered cranks, so depending on if I find splined cranks for a bargain I’ll probally go for cotterless since I’m only around a 100 pounds. Does anyone recommend a good model thats not top of the line price and also a good hub to go along with it? And I’m also confused on how the length of the cranks makes a difference. I’m 5’7 so what size cranks should I be looking at? Thanks, Joe.

Littleman, your choice of cranks should not be based on price, but on the kind of riding you intend to do. Without knowing that we really can’t be very helpful. If the riding you will do will involve lots of hopping, dropping or the words Trials or Street, you should skip the cotterless and go straight to splined. This will be cheaper in the long run.

Oh, plus you had initially said “new wheel.” Is this intended to fit an “old” unicycle? Changing hubs may mean changing bearings, and width, and only compatible stuff will fit an existing frame.

Crank length determines your leverage, and also how much foot movement you have to do. Short for speed, long for power.

How does power relate to doing anything on a unicycle? I mean I can understand speed but what do you need power for? Are you talking about riding or jumping?

power as in torque, how much force you can transmit to the wheel.

hes refering to (i think) how much “torque” you have.

The longuer the cranks the more leverage you will have and so it will be easier to go up hills and to be stable while doing trials etc. Shorter cranks u can go faster (obvious really.)