I am un disided what crank length would be best for my muni that i hope to be ordering soon what are the advantages of 170’s and the advantages of 145’s in a 24?
Ben
For MUni, I would recommend what I was sold - 170mm cranks. This will help you with climbing and rolling over obsticles.
Using shorter cranks may give you some speed and may even be more durable - but your off-road ability will suffer (unless your are just riding flat hardpack indefinately).
where are you riding? Are they really tough trials, or just so-so? If really technical, get 170s. If just so-so, get 145s or 150s. Steep inclines require 170s, as does hopping on inclines. 150s, which I use, since trails in DC suck, are good because I can make up for the lack of technical trails with speed.
I think I might go for 145’s because I don’t want a slow ass muni + they are stronger so i will not kill them on drops. It will be my trials uni while i get my hub put in my trials 19" which should be fun! I am in the uk so it’s not going to get used on the north shore or any where crazy like that but I am going to get a splined hub because it less hassle when I bend the clotterless thing’s in 5 mins!
Ben
I think 145’s are too short. You generally need a lot of torque in Muni, going uphill and down. 145’s will keep you from being able to go up steep hills. Also, you will fly off hilariously on steeper downhills as you won’t be able to stop the wheel. If you are doing cross country 145’s will be better but for real Muni longer cranks allow you to do more.
What cranks are you planning to get. If you’re getting profiles or some brand with a good variety maybe you could go somewhere in between.
Edit: I use 160’s because thats what Mojoes muni came with. They are nice. I had 170’s on my old suzue muni. I like the 160’s a lot better. I have tried Franks 145’s and didn’t like them as much.
I disagree with everything everyone else has said about 145mm cranks. Short cranks are definitely the best, and 170mm is rediculously long. I was recommended 170mm and reluctantly got them, and straight away I noticed how they make your legs swing round in huge circles, not a natural feeling at all. Short cranks will help you with climbing and rolling over obstacles because you will have more speed and momentum, and long ones will just slow you down. I don’t think short ones will be much stronger than long ones, but that should not matter if they are splined, because they are plenty strong. Short cranks rule, unicycles are slow beasts to begin with, there is no point in slowing them down even further by having huge lanky cranks that strike the ground more often and feel retarded.
This is definitely not true, you will be able to go up steep hills even faster! Same goes for downhills, especially if you have a brake to help out with the lower torque.
What hub are you getting?
This is a difficult question to answer without knowing the trails you are going to ride. You’re going to get both sides of the crank length debate and everyone is going to tell you their favorite crank length for the style of riding they do and the trails they ride. That’s not going to help you much.
If you want to do trials on a 24" muni you’re going to do better with longer cranks. Longer cranks will allow you to land on off-camber (non-flat) things and hold your position so you can do the next jump. Longer cranks will also make it easier to do things like landing on rails or logs. Longer cranks will make it easier to roll up steep tetter-totters.
170’s will make it easier to roll up curbs and roll over logs. You can’t attack curbs and logs with speed because you’ll just end up hitting the obstacle and bouncing off. You need torque, leverage, and technique to roll over curbs and logs.
I have tried my 145 mm cranks off my trials uni on my muni. I just tried it once. Yeah it was faster, but for the trails I ride it didn’t make it more fun. Instead of taking the harder line (that goes over roots and logs) I was taking the easy line on the trail. I was riding the same trail, but I wasn’t riding the trail the same way.
I have also tried 160 mm cranks on my muni. That worked better. Faster than the 170’s, but still able to roll the roots and logs and other trail obstacles.
But in the end I always go back to my trusty 170’s. The 170’s let me do steeper terrain and roll over the rocks and roots and logs.
I have Profile stuff. I’ve got 170 mm, 160 mm, and 145 mm Profile cranks. The 145’s are on my trials uni. The 160’s are on my 24" urban wheel. The 170’s are on my 24" Gazz wheel. Since everything there is Profile I can swap around cranks if I feel like it.
What I would suggest is get the same hub on both your trials uni and your muni. That way you can swap around cranks. It will give you more crank options. Swapping splined cranks is easier and more reliable than swapping square taper cranks.
There are a few trail systems in my area that would be suited for 145 mm cranks on a muni. But those trails are rather boring. The only way to liven them up would be to ride them with short cranks. Long cranks on those trails is like watching paint dry. I don’t ride those trails. We’ve got plenty of more interesting trails to ride.
so this conversation has made wonder do short cranks make you go faster or slower than long cranks? WHICH ONE IS FASTER??? i want speed!
Shorter cranks mean your legs need to do less work (well not less work, less distance), which means you should be able to turn them faster which means the wheel will turn faster which means you will go faster.
That was childish but amusing.
I agree with Rowan. My perfect setup is my 24x3" with 145mm Profiles and a brake. I’m getting a Magura HS-33 very soon second hand. I guess in the case of having enough torque to get out of ruts and over rocks and so on, the rider’s weight does make a difference.
Andrew
I am unshore now
I think that 170’s sound better but i am not shore how long it would take to get used to them as i rode phil’s muni the other day and that had 150’s i think and they seemed plenty long and what’s 5 mm… mind you I have been riding a 20" with 125’s i might get 170’s now but I do think that 145’s will be the best bet for me
Ben
Yeah i am getting the same hub on my trials it a qu-ax and i can only get 145’s or 170’s thats why i asked
Yes, you’re right.
170mm ARE too long - you can go much faster on 145mm.
Since when is MUni about speed?
Want speed? Get a Mountain bike.
Oh, this is the unicycle forum… . . .
Want speed?
Get a Coker.
LOL.
Ben, if you felt 150s were long on a MUni, then 170s will feel ridiculously long. Go for 145s - with good technique there will be few trails you won’t be able to ride. Plus you’ll be heaps faster too.
–TOny–
I personally prefer semi-slow, steep, technical stuff to fast riding and yet I still prefer my 145’s.
Andrew
See John Childs reply, he knows what he’s talking about.
As he points out the key question is what type of riding you’ll be doing and it’s meaningless to say 145’s are best, or 170’s are best without reference to that.
For me, I am averse to the big foot turning circles of longer cranks because I find it slow and ungraceful. However, I don’t do trails/technical stuff. The type of riding I do is partly dictated by my dislike of long cranks i.e. mild muni on a 23x3 with 150’s and road/mild trails with a 29-er with 125’s.
If you see Kris Holms riding North Shore Trails he’s got 170’s; obviously, as one of the worlds most experienced muni riders he knows the best cranks for what he’s ridng.
Lastly, bear in mind that it takes a while to get into any crank set up, the first few times I rode with 125’s on my 29-er almost convinced me that they were unusable; after a few more rides I’d got into the smooth, wobble free ride and speed- now I wouldn’t use any other length.
Lots of nonsense is talked about crank length. I know, because I talk a lot of it!
The ideal crank length for you will depend on a number of variables, including the wheel size, tyre section, your style, your experience, the trail, the weather, and so on.
Most people apply this simple rule: short cranks are faster; long cranks give more torque.
But it’s NOT that simple.
The unicycle is a simple machine, but that very simplicity makes the few available variable very important indeed. And every set up is a compromise. Oh for the unicycle with quick adjust crank length!
First, find the crank length which suits you for the intended style of riding. 24 with 89s
Now find the wheel size which suits.
In that order.
So, I find 150mm cranks are the longest I can ride comfortably. Anything longer is ungainly, uncomfortable, and unenjoyable. So, if I want to go up or down really steep stuff, I’m going to change the gearing by reducing the wheel size - although that introduces its own compromises.
I find that 102mm cranks are about the shortest I can comfortably spin, although I prefer 110s. So if I want to go faster, I’d rather ride a 28 with 110s than a 24 with 89s.
In the mid range, direct mathematical comparisons are useful. A 20 with 5 inch cranks will perform similarly to a 24 with 6 inch cranks (in each case, the crank is 25% of the wheel diameter) but a Coker (36) with 9 inch cranks (also 25%) would be a very different thing indeed, as would a 4 inch wheel with 1 inch cranks.
Think of yurself as an engine - a two cylinder reciprocating engine. Your legs are the pistons, the cranks are the er… crank shaft. OK, so long stroke= slow but good torque; short stroke = fast but little torque. OK, but changing the crank shaft alone wouldn’t tune the engine, because you’d need to adjust the gearing, the carburettor, the spark timing, even the fuel. So why do we assume that simply changing the crank length on a unicycle will change nothing else?
On very short or very long cranks, we use different muscle groups, or the same muscles, but with a different emphasis. We produce the power at a different rate, and possibly at a different point in the cycle.
So, get the engine right (find some cranks which suit you) then get the gears right (find a wheel to suit).
I have found that crank length has become less important as I’ve gained experience. I have ridden things on a 24 with 89s which would have stopped me on my 26 with 150s a couple of years ago.
But the simple answer: use 150s or 170s for MUni. :0)
Re: what crank length in a muni?
Mikefule wrote…
>
>Lots of nonsense is talked about crank length. I know, because I talk a
>lot of it!
Thanks for this great analysis. I’ve always been intensely interested in
crank length and for years collected all email on that subject. Maybe
one day you and I can publish a book on unicycle crank length –
imagine what a best seller that would be 
I have two Cokers – one with 140 (5.5") and one with 125 (5").
I live in a rather hilly area but even on flat stretches I don’t feel
comfortable with 5" because I feel I don’t have sufficient control,
especially in minor emergencies like bumps and quick stops,
not to speak of situation where quick action is essential. Probably
others agree with me on that,
Just my two yen.
>The ideal crank length for you will depend on a number of variables,
>including the wheel size, tyre section, your style, your experience, the
>trail, the weather, and so on.
>
>Most people apply this simple rule: short cranks are faster; long cranks
>give more torque.
>
>But it’s NOT that simple.
>
>The unicycle is a simple machine, but that very simplicity makes the few
>available variable very important indeed. And every set up is a
>compromise. Oh for the unicycle with quick adjust crank length!
>
>First, find the crank length which suits you for the intended style of
>riding. 24 with 89s
>
>Now find the wheel size which suits.
>
>In that order.
>
>So, I find 150mm cranks are the longest I can ride comfortably.
>Anything longer is ungainly, uncomfortable, and unenjoyable. So, if I
>want to go up or down really steep stuff, I’m going to change the
>gearing by reducing the wheel size - although that introduces its own
>compromises.
>
>I find that 102mm cranks are about the shortest I can comfortably spin,
>although I prefer 110s. So if I want to go faster, I’d rather ride a 28
>with 110s than a 24 with 89s.
>
>In the mid range, direct mathematical comparisons are useful. A 20 with
>5 inch cranks will perform similarly to a 24 with 6 inch cranks (in each
>case, the crank is 25% of the wheel diameter) but a Coker (36) with 9
>inch cranks (also 25%) would be a very different thing indeed, as would
>a 4 inch wheel with 1 inch cranks.
>
>Think of yurself as an engine - a two cylinder reciprocating engine.
>Your legs are the pistons, the cranks are the er… crank shaft. OK, so
>long stroke= slow but good torque; short stroke = fast but little
>torque. OK, but changing the crank shaft alone wouldn’t tune the
>engine, because you’d need to adjust the gearing, the carburettor, the
>spark timing, even the fuel. So why do we assume that simply changing
>the crank length on a unicycle will change nothing else?
>
>On very short or very long cranks, we use different muscle groups, or
>the same muscles, but with a different emphasis. We produce the power
>at a different rate, and possibly at a different point in the cycle.
>
>So, get the engine right (find some cranks which suit you) then get the
>gears right (find a wheel to suit).
>
>I have found that crank length has become less important as I’ve gained
>experience. I have ridden things on a 24 with 89s which would have
>stopped me on my 26 with 150s a couple of years ago.
>
>But the simple answer: use 150s or 170s for MUni. :0)
>
>
>–
>Mikefule - Roland Hope School of Unicycling
>
>So many pedestrians tell me I’ve lost a wheel.
>----------------------------------------------------------------------
>Mikefule’s Profile: http://www.unicyclist.com/profile/879
>View this thread: http://www.unicyclist.com/thread/30734
>
>___________________________________________________________________________
>rec.sport.unicycling mailing list - www.unicycling.org/mailman/listinfo/rsu
>
Regards, Jack Halpern
President, The CJK Dictionary Institute, Inc.
http://www.cjk.org Phone: +81-48-473-3508
Sorry John, but I think this is a load of nonsense. Curbs are relatively small obstacles, and if you can’t do rolling front hops, then sidehopping up them is easy too. You can attack curbs and logs with speed, and if you bounce off your tire pressure is probably too high, it is nothing to do with crank length. I think short cranks might be better for riding along logs due to less side to side wobble. Technique is more important than torque and leverage in most situations I think.
Haha, yeah right, John does not know what he is talking about (in this case) due to his inexperience with 145mm cranks on his MUni. If he spent a bit more time with them he would soon find himself riding hard lines on the trail even faster than before, and even lines that were impossible before due to the reduced pedal scrapes.
Amen.
Thinuniking, don’t be fooled by the lanky 170mm crank users, unless you have rediculously long legs like them. Go for what suits you best, not just what Unicycle.com recommends and what other people use. If you liked 150mm then 145mm should fit you well. Listen to Tony Melton, he knows what he is talking about.
I would prefer 180mm cranks myself, but also agree with Rowan, in that I think you should use what you think you’ll like, and my bet is that you would hate the 170’s from the sound of it.