especialy in such rough terrain i love my 140mm (26" magura) cranks cause i have much more clearance to ground / rocks
i can remember rides were my friend cant ride cause his cranks (without brake) were to long for the narrow eroded path…
Whoa, that’s gnarly! I’m trying to figure out where you are descending from, or if you just mounted near where you’re at and had the photo snapped.
Nope, I’ll happily ride things like that with my disk brake, HS33 not so much. Looks fun though!
Riding a 24" rather than my 29" down the most technical stuff is normally the best plan.
Very true - I have knocked longer cranks on rocks/ground many times where riding space is tight.
I think entropy knows what he’s doing mate! I suspect he rides long cranks because they work for his riding, not because he doesn’t know any better 
He’s quite good you know (look up some of his older posts)
Yeah, that’s some gnarly stuff, I wouldn’t want to roll that and have to rely on short cranks and a brake. But, some folks seem to prefer short cranks and brakes, so it’s probably an issue of style and what you’re used to.
I’ve ridden short and long cranks, I am now back to 165’s on my 29er and 150’s on my 26er, 170’s on my 36er. Long cranks can be spun just fine, all you need to do is ask a biker if they can spin 170-175;s 
I rode my 29er and my 26er over the weekend, and though my 26er was easier to maneuver due to the smaller wheel, I felt like the relatively shorter cranks made the uni less stable; I’m thinking of bumping up to 160’s. I like spinning the more flowing trails on shorter cranks, but on tech stuff at slower speeds I want the longer cranks to reduce bobble and to maximize power as I roll obstacles.
This reminds me of discussions over the optimal use of a geared hub for muni. I’ve seen some pics/vids of highly skilled riders managing high gear off road, but those trails are relatively tame, so I think the trail conditions really dictate what works best, though obviously skill level plays a part. In Entropy’s defense, no one is riding that sort of DH with short cranks, not even Kris and his peers.
Anyone who runs a brake knows that there is a downside to short cranks: brakes can not incorporate balance and speed control, so you lose fine control over the wheel. Also, brakes tend to grab and can force your wheel off line, esp disc brakes which pull the wheel to one side.
With long enough cranks I can ride a tech downhill on crank power alone, but I can’t say the same with short cranks and brakes.
Now that I have long cranks again, I have more control on the down, more power on the up, and I use the brake less.
That previous pic is of Eyal from five years ago; he is indeed descending along a trail, albeit carefully. These days I tend to 29er that sort of terrain.
I would point to this post by Kris about crank length. The backstory for the trip is that we forgot to bring his muni on the second day in Squamish, so he was borrowing Eyal’s for large sections.
That said, muni setup is definitely all about what works best for you and your trails. I tried short cranks for a year or two once upon a time and unlike a lot of muni folk, I did not enjoy it all that much. I found that pedal strikes were easily averted by taking the high line. 
A rim brake never was and never will be an option (true rims are for riders with technique :p), but my knees might someday be convinced to try a disc brake on the 29er.
Bringing my foray in this thread full circle: I’m clearly in the minority with respect to crank length; rugged long cranks (above 165) are difficult to find! 
Hey Entropy, you’re not alone in the long crank perference 
Like you, I tried shorter cranks, and though I liked them in some ways, like smooth spinning on my 29er, I found they just didn’t provide the same level of control and power I was used to, so I went back. I have 165’s on the 29er now, but prev ran 170’s.
In terms of knee pain, I think short cranks increase knee issues. I started having knee issues last year AFTER I started playing with short cranks. At first I thought it was an offset thing, riding with my feet to close together, but I am not convinced that the short cranks were putting excessive pressure on my knees during climbs and descents. Since going back to long cranks my knees have been fine.
For ISIS splined hubs, there are a number of trials cranks that can be had in 175, maybe even 180. I’m looking at some 175’s now, just need to find a place that has them in stock in the USA; most are in the UK.
ISIS Crank choices: QuAx Chromoly Tubular Street Cranks 170mm, I run these on my 36er, super durable and lightwieght.
Trial Tech 175: http://www.biketrial.si/shop/product_info.php?products_id=80
Tensile COmp or Urban 175: http://www.rocknrollbikes.com/trials/cranks/tensile-comp-cnc-7075-trials-cranks.html#Size=170mm
Onza 175: http://www.rocknrollbikes.com/trials/cranks/onza-comp-pro-crankset-160mm-175mm.html#Length=175mm%20Titanium%20Grey
Middleburn 165-180: http://www.middleburn.co.uk/cranks_rs7.php
Brothers in (crank) arms. 
I’ve had similar thoughts.
If you do find a source in the US, post a follow up. Lately I’ve had to rely on imports to maintain my habit.
Oh I’m not doubting that, I was just making the comment that my idea of aggressive downhill is no different 
um- but he also admitted to not using a brake. I will admit, that if 90% of the trails that I rode all the time was like the one in entropy’s picture i’d be on a 26 with 150s and a brake. Contrary to what some people think, when you can actually use a brake in technical downhill (instead of just drag braking on a slighter, more constant slope) you have MORE control than with leg power alone. It takes a long time to get to that point- but it once you do, only then will you understand.
At UNICON in wellington in the Super DH course I was one of only a very small group of riders who cleared a particular section of really steep, ledgy, loose and rooty trail in the actual race. Even David W (Current World Champ who does not run brakes struggled here). You can see the footage in this vid at 1m 30.
I agree that in some circumstances brakes are a compromise. For example, when I was using 125mms on my 24"GMuni. They were just too short to be appropriate for super gnarly DH- even with skilled braking. That was a compromise I was willing to make because I very rarely rode purely DH muni. But to say that brakes can not incorporate balance and speed control is ridiculous! What are they there for then? To look good?! Any day of the week i’d take a 26 with 137s and a good brake than a 26 with 175s and nothing.
Different strokes/different folks- But I think a shorter crank+ brake set up is going to be much more versatile for most riders,
Mark
Again, I think the biggest factor is what type of terrain you prefer to ride. Sure, if all you do is DH or XC, then 137’s on a 26 might be fine. However, some of the hills I climb are fairly difficult with 150’s on my 24. I’d be surprised if many riders could clean them consistently with 137’s on a 26.
Also, I don’t think Kris was stating that brakes don’t give you any balance or speed control. However, shorter cranks mean less leverage, and that equates to giving up a certain amount of speed control and balance. With experience, a brake can compensate in some cases, but not all.
For the most versatile setup, I think average crank length and a nice brake gives you the most options. Shorter cranks are always going to limit your climbing and hopping ability.
I don’t think any of us can deny that longer cranks can have some advantage on some terrain and with practice, a brake can also provide a lot of control.
If cranks are too short then I also agree, there can be times when your feet also need to play a part in control on uneven dropoffs etc and this would be more difficult, but even more so without a brake at all.
I’m still dubious about the grabbing comments, yes my HS33s grab very slightly more in some places on my 24s rim than in others, but I’ve never found it throw me off-line, merely a bit too far forward or back.
With my disk, I have as of yet with plenty of riding on it, not experienced any kind of pull to one side or the other - presumably the only way you would get this would be twisting of the frame due to more of a pull on the disk side.
The disk most definitely voids the fine control comments though, once you’ve learnt the bite point of your lever, fine control can be absolutely fantastic, in some ways better than with your feet as you can brake in between pedal strokes.
This obviously depends on the rider - and we can’t judge anyone else here.
The larger the wheel, the slower you have to pedal to maintain the same speed which can have a large effect on traction going up a hill. Longer cranks can also enable you to power over larger bumps going uphill but as far as smooth hills go.
I find keeping momentum and a more even pedalling rhythm going up hill far preferable to trying to slow down and power up with longer cranks (even on the steeper climbs). I’ve always been a bit of a hill racer
When did we get onto long cranks and uphills anyway?
sorry for responding late.
yes the Gazz is a 3"
yes it is a Mad4One hub.
now the problems with the 26 is that the tire is a bit heavy, so the inertia is a bit like riding a Coker. I started with 140mm cranks which were ok for trails and easy descents but not with technical trails (terrible UPDs ensued).
I have been trying 160mm cranks but I am not sure I like this length :o
(should I try 150?)
about the kneee-pain discussion:I concurr that shorter cranks are bad for my knees that’s why I went back to longer cranks (on Coker and 29") but 145 is ok for me on the 24/3 but the 160 are also bad for my knees on the 26/3.8 so I suppose it"s a more complex rule.
I love 150s on my 26X2.7 its smoother spin than 165s and more leverage than 140s
Really, hmm, I guess then all the DH bikers and trial bikers shoudl consider shorter cranks, eh?
Don’t confuse your personal preferences with physics.
Long cranks provide more control and power than short cranks, brakes offer more control than no brakes, therefore using short cranks and a brake will provide less control than using long cranks and a brake.
You can like your short cranks for what they do well, but don’t tell us that short cranks can do the same as long cranks, it’s just not true. Long cranks have an advantage over short cranks for power and control, just as short cranks have an advantage over long cranks for weight and smoother spinning.
A skilled rider can always do with less, but even Kris admits that long cranks have their place…
I’ve used both, recently, and I chose to go back to long cranks because they are less stressful on my knees and they give me more control. Granted, I’m not trying to ride tens of miles, and I sometimes miss the smoother spinning short cranks, but I like what I like and I’m not alone. Aspen Mike, you know the name, rode up a certain volcano, lots of skill, been doing this for a while, he rides a 29er with 175’s and no brake 
absolutely.
when it comes to knee pain I think that I am not a skilled rider so:
- when cranks are too short I try to correct trajectory by small lateral movements that are bad for my knees.
- when they are too long the same thing almost happen (because I spend too much time in vertical unstable position? I don’t know)
well it’s just a theory not real physics… (I work for a physics department in an university and they are going to kill me if I tell stupid things :p)
Coming from an XC MTB background to MUni crank length has fascinated me due to the obsession with short cranks.
For my MTB hobby crank length was decided based on anatomical fit, Your bike and your chosen riding position decided your saddle height and fore/aft position this fixed your hip location meaning you then chose a crank length relative to your thigh length so your knee cap was in-line with your pedal spindle (using a plumb bob).
Having limited crank lengths to choose from you could move your seat fore and aft and change your handlebar stem length to compensate and correct the reach.
This ensured you didn’t stress your knees, so whilst on a Uni things are a bit different I am sure the premise must hold true to a point, but we have to push the envelope to improve the ease of spinning circles smoothly at high rpm
I would be keen to try some nice light ISIS trials cranks in 175mm my new KH20 trials has shown me what feel you get from “big cranks” (relative to the wheel).
I maybe talking guff
I would agree that both long and short cranks have their place. However, for the current state of unicycling gearing, I believe that shorter cranks are more useful. Since we only have un-geared and a very limited geared system (however awesome you might think it is, it is quite limited), longer cranks just don’t have a big place right now. I understand that longer cranks might be ergonomically more efficient (I ride a road bike too, it has 170s), but that is irrelevant until we have better gearing systems.
Just my personal opinions. I don’t use cranks longer than 140mm on any of my unicycles, including the geared ones. Also, I feel out of control with really long (160mm+) cranks. I know that is partially because I’m used to shorter ones, but the smooth, smaller circles feel more in control than the bigger wobbles, which make me feel like my legs are going all over the place. I would argue that short cranks encourage a different kind of control than long cranks do. I’m always amazed at the amount of control I can have on my freestyle with 89mm cranks, but the control that I have is quite different then the control I would have with 125mm cranks. Also, I would not categorize myself as a top freestyle rider.
Also, you don’t need a brake when you’re riding uphill 
Oh Ben- you do like a good old debate don’t you! I prescribe everyone caring about this 3hrs out on their unicycles having fun! That should fix the bickering.
I went out for a really nice ride yesterday with Jamey Mossengren and Rob O’brien out at the MTB trails at Awaba (about 40min south of Newcastle). We started off with a 12km loop of fast, flowy, and occasionally steep and tech single track. Then after a morning tea break hit up the Downhill course which was pretty fricken badass. Lots of super steep, rutted, and rocky descents, narrow rock chutes with ledges and some big jumps/drops. It had been drizzling on our way up to the top so we had to avoid some of the A lines because the rock slabs and wooden boardwalks were simply too slick to ride.
We were all on G26er Munis with 137mm cranks (any longer than that and we would not have been able to clear the narrow technical sections due to pedal strikes) and the ardent 2.4 folding bead tyre, 47mm freeride rims, and Muni handlebars (of various configs). I didn’t miss my dedicated DH muni at all- the 2.4 was every bit as good as the bigger 3" tyre and the 137s combined with the rim brake had lots of leverage/control. The extra rolling ability of the 26er over the 24 helped avoid getting the wheel jammed in divets, or against larger rocks.
It was so much fun getting back to my DH roots- i’ll have to head back out and make a video of the run because it really is in such a spectacular area. My G26er is a true ‘quiver killer’. It does it all so very well that I don’t need any other unicycle for off roading. Yes, that does mean every now and then you are compromising a little bit here or there- but i’m the kind of guy that thinks that stopping to adjust your seat height during a ride is for wieners who are just trying to find an excuse to have a rest. I want a uni that will ride everything, with absolutely no fiddling about- the G26 gives me that.
Mark
Man, I haven’t ridden with Jamey in ages. Actually, I think this was the last time. Glad to hear he’s swapped his break for a brake.