After a summer of riding a 36’er with 110’s, I decided to replace the 150’s on my KH24 with 137’s and see how it felt on technical downhill on the Vancouver North Shore. I’ve used shorter cranks before for XC riding but never on harder stuff.
Only one ride so far, but I really like it and am going to stick with it for now. Descents feel much smoother and it is easier to spin out off the bottom of transitions. Also cornering is smoother and it is nice not to worry so much about hitting pedals on the ground.
Big caveat: Using this setup for technical riding really benefits from effective use of a brake, especially with a Spooner on it. I felt like I was depending on the brake for most of my braking power through transitions and quick stops. It’s nice to do that anyway with 150’s but with the 137’s it actually felt easier to brake while pedalling through bumps.
Also, it is easier to get used to this if you are already used to pushing shorter cranks on a 36’er.
Just thought I’d pass that along. Anyone else tried this setup?
I can see the speed advantage of 137’s over longer cranks, and less up/down leg movement for DH, but I love climbing as much as DH, so I’ll stick with my 150’s for now. If doing mostly DH, why not go even shorter, like 125mm?
I have been wanting to throw some short cranks onto my muni for a while. I am without hub at the moment… no pun intended.
I do not have a lot of muni experience tho I have been giving much thought to working on some fast paced freeride type stuff. http://www.vimeo.com/810530 this was my first attempt at Muni with tricks, tho I ended up thinking, even tho I am much more comfortable on a 19" that the speed advantage of a 24" for that kind of riding would be a great addition (with much practice of course). However with Muni longer cranks hit rocks and would aslo jolt the rider around more. So short cranks would help smooth things out a little as long as the rider has no fear and good brake control.
Glad you posted this Kris, It will help inspire me to build up my muni again with shorter cranks and a brake.
I think what it comes down to is what works best for you. One size definitely does not fit all. Some even prefer 170mm for the added torque and for climbing especially long, increasingly steep terrain. Others, like Kris H., preferred, and recommended the 150’s for the longest time.
I started with 165’s back in '05-the same size used by at least 4 (and likely many more) of the best MUni riders in the LA/SB area-but since changing to 150’s, I would not go back to the longer cranks. I find the 150’s to be the perfect size [for me] for doing steep climbing, rolling technical terrain, natural trials… and they allow for plenty of speed, adequate torque and less need for braking, and they’re also great for drops of any size. But I suppose if you’re primary focus is downhill, than 137mm might be the way to go, or even shorter. Well, that about sums it up for me.
I have tried 137’s…on a KH 29er lol! It was before I bought a 36er and that’s all I had to keep up with the big wheels, but I was able to keep up fine. I just pedaled way faster! IT was all on flat, beach path.
But, for me it’s about control as well, and the 150mm give me all the things I mentioned, and less need for a brake on steep DH.
There was at least one thread a while back about whether logic & physics should be thrown out the window, with some people stating that shorter cranks are just as, or even EASIER to climb the same steep terrain as longer cranks. There is no question that the shorter the cranks, the less leverage you have and the more pedal force it will take to climb.
If anyone disagrees, than I don’t know what to say lol! There are still people who believe Elvis P is alive & well, and that the earth is indeed, flat! Oh, and just for the record, I know you didn’t say that in your quote above, but it just kinda me of the old thread.
I think it has a lot to do with the difference in feeling between when you first jump on to a uni with short cranks, and when you actually get used to it. After a lot of riding on a 36’er with 110’s, climbing steep hills on a 24" with 137’s felt just as easy if not easier than how 150’s used to feel.
But for technical riding it really does depend a lot on your riding style. If your style is oriented towards rolling through technical sections, shorter cranks are great. If you want to slowly hop and work your way down, you won’t run up against any limitations in spinning anyway, so longer crank would be more appropriate.
Plus as I mentioned it is a lot easier to use shorter cranks with brake because the limiting factor for technical riding with short cranks is not climbing, it is quickly stopping or preventing too much acceleration.
I see the key word there is “feel”? So, would you say that 137mm feels/is easier for steep climbs than, say, 150mm, does that also hold true for even longer, 170mm cranks? If so, can we assume that the shorter the cranks, the easier it is to climb?
Taking it to the extreme, would not even shorter cranks in the 100mm, or even 89mm make climbing even easier? In other words, where is the “cutoff point” in shorter cranks going from being easy/easier to climb with, to being difficult or entirely impractical for steep climbing? I’m being facetious, but I’m just trying to understand the reasoning that shorter cranks “feel” or indeed are, for some it seems, easier for climbing.
Maybe I’m mistaking “easier” for more efficient? I mean that even though you may be expending more force to get up a hill using a shorter crank, maybe it’s just “easier” in the sense that your legs are making smaller circles and you are concentrating your energy-albeit a greater amount-in a more efficient manner?
I think shorter cranks feel more controlled when spinning fast, and I think most people that spin fast would agree. I agree with Kris’ point about riding style. My style is definitely more rolling and flowing oriented than stopping a lot to hop over/through obstacles.
The physics of a unicycle and unicyclist is quite complex. There are a lot more factors than just leverage to consider.
I never said 137s are better for everyone. You can argue all you want using ideas from physics, but trying them out is the real test. I’ve tried 137s, and I really like them. Who really cares about the underlying reasons that 137s feel better?
HAha I was only referring to climbing with shorter and shorter cranks, and that some people were declaring that the shorter they [cranks] are, they are somehow easier to climb with. Maybe more efficient yes, but more pedal force is required than with longer cranks. That’s just a simple fact. Less leverage=more force required.
You referred to SPINNING FAST, meaning DOWNHILL. Lol, I know that the shorter cranks are great for DH, as KH first posted about in this thread. I love spinning fast too…especially with a camera in my hand shooting POV! It was only the uphill aspect that I was talkng about, and that if your primary focus is “spinning fast” downhill, then hells yeah! Shorter cranks rule!
But for me, I like climbing and everything else, so a good, muilt-purpose 150mm is just right for me.
The shorter the cranks, the less torque you can get on them. I’ve been riding my 29er with 102mm cranks, going from 125mm. I’ve had trouble getting started due to the length of the cranks. Its not about what length is “easier”, its about adapting to what you have. Granted I haven’t ridden in a few weeks, it is still a bit difficult to static mount with 102mm cranks (correction: mounting is no prob, its getting her rolling is the problem). There would be no way I could climb a steep hill with 102s, I’d detour that hill, and look into getting back to the 125mm cranks I was used to and could climb.
Haha, ok Rhett!
Like I said, “feel” is the word. But sometimes perception is reality! I do think you’d be singing a different tune if you tried climbing with 89’s…but then again, maybe you’d find those the easiest of them all! I mean, anything is possible…in the bizarro world!
For sure the key word is “feel”. It’s hard to be quantitative and useless to argue that one length is better than another in an absolute sense, because with experimentation everyone will arrive at the crank length that feels best for them.
However, many riders have never experimented with crank length because most riders don’t have the luxury of owning every wheel size and crank length option available.
The main thing about using shorter cranks for technically hard riding is - try it for long enough to get used to it and you just might like it. If you don’t then whatever- it doesn’t matter. There is no one good crank length but there are one or two sizes that will be preferred by most people, most of the time. And try it with a brake!
I’m looking forward to getting my new KH24 with 150/125s and a brake. The brake will give the stopping power and I’ll be able to adapt to lots of terrain. I think that double hole cranks are the way to go on a muni now.