Shock short cranks can climb really well!

Unicycles and Equipment
1

I have recently switched from a kh26 to a kh29 as some of you may remember and I have been playing with crank length since the switch to try and find the perfect crank for me as I ride on some pretty big hills (it is a rolling up and down landscape hardly any flat a all).

I started with 170m as this gave a similar ratio as my 145mm or my kh26 now this gave a godlike hill climbing ability but I was disappointed that is was so slower with the massive circles I was having to turn.

I have now done some 20 mile rides on 137mm and the Uni flys along! What I was suprised at was how well it climbs, it is hard work but th big wheel rols over everything and the shorter cranks keeps your speed up so you carry the momentum better.

Also standing up and slogging up the hill is incredible, it is so much easier and faster, the shorter cranks are being pumped in the same sort of start stop cadence as on my kh24 and then kh26 but now each stroke propels me forward so far you fly up the hill, also the short cranks mean you don’t more about so much so the uni feels more stable so it is easier to balance (and combined with the roll over effect of the big wheel it is pretty epic).

There is a loss of control and I am having to brake far more (I am increasing my rotor size as the 160mm is struggling and so is my braking finger) as I can’t stop on a button with just my legs like I used to and hill starts are tricky as you try and pick up momentum and hit a big bump etc (mounting is far easier I find(

Like I said it is hard work and the short cranks make you earn the advantages but they really do feel good and the 137mm cranks have taken me buy surprise.

My Uni is almost perfect :smiley:

2

Just get a 200mm rotor and be done with it, I have 200mm on all my unis, they work great, just don’t forget that you need the adaptor too. Shimano makes a good rotor for a fair price, don’t blow the csh on Magura unless it’s on sale.

I’ve been down he short crank path, they make for a nice spin, but they aren’t for steep climbs, you just can’t get enough leverage, same goes for big downs, you’ll need a big rotor cuz 137’s have no stopping power.

3

Shorter cranks have less of a dead spot which makes climbing easier… I normally have 125’s on my 36… I have even climbed a few hills with 110’s

4

Relatively short cranks ARE for big climbs too. Like 1500 meter climbs in the Alps. I would qualify 137s on a 29er muni as pretty short, but you would be amazed what you can get up. The key is not slowing down too much and “clomping” up the hill like you would with longer cranks. You have to keep an spin going.

5

I like getting to the top of steep hills as fast as possible, so on the steepest ascents, I always ride my G26er in high gear, and of course, I use the 110mm hole to make it faster and easier still! ;):smiley:

6

Finally someone understands. :smiley:

7

I am loving them more and more with every ride :slight_smile:

Standing up and slogging on the steep stuff like I used to on my single speed MTB is so much easier, and as has been said you keep the speed up to keep the big wheel rolling and you fly up the hill far faster so get it over and done with.

I also love the leg ache the next day as I am using all those new regrown muscle fibers I tore up on the hills as I know I worked hard and my legs are growing and adapting (like when I used to weight train).

8

Try getting a schlumpf and ruding up hill in high gear :slight_smile:

9

Short cranks are especially awesome coming down the hill, you have much less power and control, so there’s less risk of wearing out your legs :roll_eyes:

I have the following ISIS cranks in my gear box: 125, 137, 140, 150, 160, 165, 170, 175, 180 (yup, Truvativ jump cranks). I played a game last year with my 29er, every couple weeks I would reduce my crank length, I started with 170, went all the way down to 125’s, giving each their due time to shine.

What I found was that my hill climbing was harder with short cranks, most hills were still doable, but it took more effort and in some cases I was unable to climb as far on tough hills so I walked more. I admit the spin and cruising of the shorter cranks were a nice change, and I would even have been willing to give up some hill climbing ability, until the real downside of short cranks came to my attention: everything that goes up, must come down.

I found that reducing the length of my crank also reduced the leverage I had to control my descents, so I had to rely much more on the brake or risk damaging my legs. At the same time I also noticed that short cranks lacked the leverage to adequately manage technical terrain. The biggest difference was when I went below 150mm, a length that I found was a good middle ground for XC

Next I decided to play the same game in reverse, gradually working my way back up to the grand length of 180mm, a length I found to be incredibly powerful but kinda wonky to ride, ultimately I found my sweet spot in the 165’s :slight_smile:

Unlike most riders, I run the same 165 crank length on all of my wheels (26, 29, 32, 36), my reasoning is simple: by minimizing the differences between the wheels, I am better able to adjust when changing from one to wheel to another. I often ride more than one wheel size in a day, so being to jump from one to another without having to adjust is too cool; I also run the same saddle, handle, and rotor size/brake.

Granted, the 165 is a bit of an overkill for a 26er, but I only use that wheel for DH and fat tire riding. In the 29er a 165 lets the wheel be a master of tech riding, providing super power and awesome terrain bridging, while still not being excessively wonky for spinnier trails. On the 32er and 36er the 165’s give me the power I need to make a big wheel do the muni :smiley:

For riding in areas where the hills are flatter, riding road, sure, I could see using shorter cranks, but not in Appalachia, ya’ best take your sissie little cranks and go on home.

Just my .02 :stuck_out_tongue:

Have we not burned out this subject yet?

10

150s work great around here on 29" and 26" off road. 137s may work, but I just couldn’t get in the groove. Things get a bit steep pretty quickly.

If you’re feel heroic, 100s can work on the 36" for road riding. 110s are sensible.

This might be handy information for some people in July of 2013. :slight_smile:

11

I agree that for a 29" Muni, 137’s are the best! Just like Scott said, as long as you keep your momentum going…

12

But does that actually minimise the differences? Personally I also often ride more than one wheel size in a day - quite often all 3 different sizes I have (or given I now have a Schlumpf, arguably that makes for 4 different sizes!) I only have 2 crank sizes, 125 and 150 (well 152.5 on the Schlumpf, but that’s as near the same as 150 as makes no difference). Now I’d argue that my 19er with 125s feels far more similar to my 26er muni with 150s than my Schlumpf 29er with 152.5s does. Not that I find it a big deal adjusting from one wheel size to another - the trick with that I reckon is often riding multiple sizes back-to-back (if I’m trying to transfer a skill I’ve learned on the 19er to the muni then I’ll be jumping from one straight onto the other, and right now I’m going straight from practicing changing gears on the 29er to practicing rolling hops on the 19er). Anyway, there are multiple different sets of programming in use when just riding the 19er - forward riding, idling, backwards riding, hopping…

13

offset vs straight cranks

I bought a coker with 150’s a couple months ago. I was curious so I put a set of 170’s off a torker on to see. I found more power and less side to side wander at speed. I then put 150 torkers on and the wander is still gone. The cokers are offset and the torkers are straight. Other than ankle clearance am I missing anything? This is only ridden on the road. thanks jon

14

The Q factor (offset as you refer to it) does have an impact, zero Q factor (straight) cranks are easier to spin with lsee side to side motion on the Uni, where cranks with some Q factor give a wider stance so add side to side stability on the Uni but can be harder to pedal fast without weaving / wobbling.

Another issue I have with zero Q factor pedals is it increases my chaffing saddle issues si wider cranks help to alleviate that

15

Jona wrote:

Feisty wrote:

I ride the 125mm spaced Nimbus hubs with 165 KH Moments on all of my unicycles (26, 29, 32, 36). My total pedal spacing is more than an inch wider than a 100mm standard uni hub with low Q cranks, and yet I have no more wobble that I did on any other unicycle. I think what Jona experienced was more due to adaptation than anything related to Q factor. Like a bike, we can learn to spin smoothly on a wider platform, it’s just a matter of compensation.

I prefer a long crank and a wide platform because I have more leverage for climbing and for doing technical terrain at slow speeds, not unlike mountain bikers or trials riders.

I do think there is a point of diminishing returns, but for each person that point is different. Aspen Mike rides 175’s cranks on his 29muni and three position 175- 150-125 cranks on his 36er, no brakes, and he is one amazing rider. I have ridden up to 180’s, did an extended period of riding on 170s, but for the past six month I settled down to 165s on all my unis.

16

[QUOTE=Nurse Ben

I ride the 125mm spaced Nimbus hubs with[/QUOTE]

I am really tempted to get a custom e 29er made for this hub as I can’t find any short high Q cranks and the wider my feet the more comfortable my crouch is

I could get an Oregon I suppose and run a 29" wheel but I can’t get the frame on its own and I am not a fan of the tube style either.

Custom Triton perhaps with green oracal hub, seat collar, nipples etc :wink:

17

UDC USA sells the frame as a separate, does the UK not?

The doube leg tube frame is awesome, no knee knocking ever! Plenty strong and not any heavier than a typical single leg frame.

My 36er uses the same frame design, but with a frame mounted caliper. I had an Oregon frame with the caliper mount welded on, but it was wonky so I traded it for the new style with a D brake mount. If I ever decide to paint the Oregon frame, I may have a mount added, though I think a custom Hunter would be pretty cool; double leg also.

If you wait until Spring, the revised Oracle 29" frame should fit the Knard tire and it’ll be a standard width hub. In terms of wider cranks, Try All is pretty wide and they come in 160-175, not sure about anything shorter.

18

I have some 170mm tryalls and they were very comfy but far too long but did highlight my saddle discomfort (after changing and modding saddles numerous times) seemed mainly to do with Q factor (or lack of)

19

I’ve used virtually every crank size from 170mm down to 75mm and a few years ago I went through a period of being obsessed with riding the shortest cranks I could manage.

Yes, with short cranks you can spin faster on a flattish smoothish surface. However, changes of speed are more difficult, and short cranks make descents more tricky than ascents.

What worked out in the end was that you are using a shorter range of muscle movement with shorter cranks. That’s great if you’re not having to put much oomph into your riding (cruising on the flat) but if you’re riding hard, then all that effort is focussed on a small fraction of the muscle movement that is available, and you tire more quickly.

Changing the cranks isn’t like changing gear: it is more like changing the stroke length of the engine - a fundamental change in the way that you produce the power.

Note that bicyclists with freewheels and multispeed derailleurs could use any size cranks they wanted, and you don’t see people in the Olympic sprints or on the Tour de France riding with 110 mm cranks. There is a reason why they choose cranks around 160 - 170mm and then choose the gears accordingly.

A uni is not exactly the same as a bike, and I find that while I can spin 165s on the bike, I prefer 150s on the uni. I can ride my 28 on 75s, but only by making lots of compromises. There is more versatility in choosing longer cranks and learning to spin them faster. The long cranks will get you up and down hills easily and safely, you will ahve good control, be able to change speed easily, you will tire less, and although you will lose out on top speed and “cruising speed” you won’t lose much, if anything, on total journey times.

20

It’s incredible how your perspective changes - I was thinking that seems an incredibly long crank, but then reminded myself that it’s the only length cranks (within a couple of percent) I ever rode for the last 25 years until a year ago.