My 29er is a Bit Twitchy

Ok, so this is maybe an odd problem.

I started riding 10 weeks ago. I ride every day. My first uni was a 24" Nimbus on a Maxxis Hookworm tyre with 125mm cranks.

My next uni was a 26" Pashley muni with a Maxxis Hollyroller tyre and 125mm cranks, courtesy of Mike Fule.

I can ride both comfortably over a reasonable distance, say 2 - 3 miles. My legs are jelly at the end of the ride though, which is probably normal at this stage.

I’ve also got Mike’s old Nimbus 36er. This is also nice to ride, once I’m up there.

The issue is that I’ve got a 29er Nimbus Oracle on a Schawalbe Big One tyre, on a light but wide-ish MTB rim, running tubeless. Cranks are again 125mm.

The issue is that the 29er feels skittish underneath me. I’m forever speeding up or slowing down. It’s exhausting to ride. Is the issue that the cranks are a bit short relative to the wheel radius, for an inexperienced rider, or is the wheel a bit too light, again, for an inexperienced rider? I’ve covered maybe 15 + miles on it over several weeks and it doesn’t feel as though it is getting an better.

Any thoughts on how I might improve this situation would be great.

Put your seat as high as comfortably possible. You know the rule for setting the seat height on bicycles: sitting naturally with a comfortably straight leg and your heel on the pedal gives you the right height. I find a tad lower works better for the unicycle - maybe only 5 - 10 mm lower, but it makes a difference.

Sitting tall in the saddle will make the uni more stable - think of it as a Sitting tall (bum in, head up) gives it a longer period of oscillation.

Keep your weight on the saddle, not on your legs. Even a “huge” 36 is only equivalent to below bottom gear on most road bicycles, so your legs shouldn’t need to be working hard until you get to a hill or rough ground.

Think about keeping the unicycle under you rather than keeping yourself on top of the unicycle. My older son says this is the piece of advice that helped him most.

Think about that thing where you balance a broom on your finger. Small gentle movements of your hand will keep the broom balanced with very little effort. If you make big movements, you will need to correct them, then you will overcorrect and you will start to waste energy.

Look at the ground 20 or more metres ahead, or even at a fixed point in the middle distance. Looking down at the ground immediately ahead will make your balance worse, translating into harder work for your legs.

When I was learning, I looked for places like parks or nature reserves where I could ride on smooth paths until I was bored, then on rough ground or rough paths until I was tired. I could then alternate between the two, getting the useful practice on the rougher parts and getting my breath back on the smoother parts. The more you ride, the more things will come within your personal definition of “smooth ground”!

I also found that brief bursts of “top speed” between longer sections of “just cruising helped”.

The last two techniques (smooth/rough or fast/slower) work on what I’ve heard rock climbers refer to as “the dance floor effect.” They climb to a precarious ledge. They then climb up to an even more precarious one, and retreat to the original one to think about their options. Each time they return to the original precarious ledge, the easier it feels, until eventually it is “like a dance floor”.

Also, find an area like an empty car park, tennis court etc. and set out some markers (cones, bags, your jacket?) and ride figure 8s so that your brain starts to work on the steering and forgets that the fore/aft balance is difficult.

As with all balance and fine motor activities, the end goal is to take your mind out of the equation and leave your brain to get on with it. By the time you’ve consciously thought of something and put it into action, the moment has gone.

Good luck, and have fun with it. If you are confidently riding a couple of miles at a time, you have already achieved more on a unicycle than most people in the world. You’ve done the difficult bit, now it’s just refining and developing it.

I’ll way in and maybe some with more riding experience can comment. I’d expect the lighter tire/wheel on the 29er to be part of the cause of forever speeding up or slowing down to maintain balance forward and back.

I read a lot of comments about folks going to great effort to cut the weight of unicycle tires and wheels. To me that makes no sense on a commuter/touring unicycle. The heavier the wheel the easier and less effort it should take to maintain balance both forward and back and left and right. With a lighter wheel the more the wheel has to be moved forward and back under the rider to maintain balance. With a heavier wheel just attempting to peddle a little faster without actually moving the contact point in relation to the rider will maintain fore and aft balance. The greater rolling momentum of a heavier wheel also helps to roll over bumps and dips with little effect.

In the sideways direction the heavier wheel weight and more speed greatly increase the gyroscopic effect. This helps helps to maintain balance left and right. Yes, the heavier wheel is harder to start and stop rolling but that is a very small part of a road trip.

Am I missing something here?


I agree with you completely Jim. After riding my 36er daily for the past few months I jumped on my 24 last week and I couldn’t believe how jerky I was at first keeping the wheel fore/aft. The heavy wheel of the 36 under way is really like walking. Falling forward you momentarily put more weight on the front foot and vise versa. The inertia of the heavy wheel creates a pretty solid resistance to balance from.


I figured I’ll play the Devil’s advocate on this one, as I absolutely love the feeling of ‘skittish’ wheels! They’re hard to get the hang of but they’re ridiculously snappy once you get into it. I find heavier wheels/tyres are ridiculously tiring for riding long distances, and not only because they make mounting and accelerating harder. My G29 has a Nimbus rim and a Marathon Supreme 2" tyre (Which is nowhere near as lightweight as it gets!) - in low gear it feels like skating on ice, it’s smooth as anything and I can stop and turn on the spot without even thinking about it. I’ve even been looking into building it onto a lighter, skinnier wheel… if only I could afford it after the ruinously expensive hub :smiley:

The weight is obviously a factor, BUT you’re running a ‘wide-ish’ MTB rim and a Big Apple tyre. This isn’t a ridiculously lightweight setup, and 125mm cranks aren’t really short for a 29er of this setup (Plenty of people run 125mm on a 36er wheel without issues).

The main factor for the ‘skittish’ feel is most probably that buttery smooth Big Apple tyre - they’re renowned for having impressively low rolling resistance for their width, and even on wider rims it’ll have a really round profile that’ll make cornering have that same skittish feel. This means you’re not really fighting against anything when you push down on your pedals, but because you’re probably used to doing so on your other wheels, you’re pushing harder than you need to.

I wouldn’t change anything about your setup - just keep riding it, and practice spinning ‘weightlessly’. It’s a really weird thing to practice but I find riding no-handed helps a lot (Otherwise I end up pushing too hard with my hands which in turn makes my legs mash down harder). If you have anything on your back, try clinging onto the straps near your armpits, to give you that schoolkid walking pose - this’ll stop your arms waving all over the place but also stop you from using them to mash down on the pedals.

I don’t want to sound like I’m an expert, but I rode my ungeared 29er with a similar setup for years and I really got used to it (and really fell in love with it) so hopefully my insight is worth something :smiley:

I know exactly the feeling you are describing. When I take my off road tire off my 29er and put my big apple on it feels the same way, I can’t stand it. I would say that it is mostly due to your tire. (in my situation it is 100% my tire, when I switch it to something heavier with more rolling resistance it feels right again to me). Two options, either switch to a different tire or keep riding, you will eventually get used to it.

Yeah so basically you’re saying to get the Hatchet, which has a true fat wheel and it is quite heavy. Very easy to mount and can practically stand still upright. If only… It is so heavy that after a shorter distance that a Nimbus 29" muni, it eats a lot of energy. When I’m tired I also start to sway forward and backwards more. So it is not just a heavier wheel. I have no probs with the 29" and last year rode 20km with it up and down hills. I was quite broken after the trip, but no swaying.

Mostly it is just saddle time. The longer you ride, the better you get a feel for the movement of the uni.

Put in more time to develop the correct muscle memory. 10 weeks is nothing.
Your story sounds normal to me.
Give it another month.

Same here. I don’t mind having to interact with the wheel while I’m riding. That’s kinda the point, from my way of looking at it.

A lot of people have found that it’s easier to ride up a slight grade, and I think that’s mainly about being able to ride with steady forward pressure on the pedals. Pedaling with back pressure is something we do a lot less and aren’t as skilled at doing accurately and smoothly. When I get sloppy, I find myself checking up too much, then having to speed up again, then checking up too much again, etc. That’s annoying and also a poor use of energy. Riding faster also tends to be smoother since there’s more resistance so it’s easier to make front-back balance corrections just by pedaling forward less hard. I noticed right away how much easier this was on a 36" wheel when I got my Coker.

You might try spending some time riding down moderate hills where you can work on using steady back pressure to control your speed. See if you can keep a constant speed, not speeding up, slowing to almost a stop, and speeding up again. It takes a bit of a delicate touch on the pedals but I think that’s worth developing and helps in all riding situations.

But yeah, switching to a fatter, heavier, less freely rolling tire is an option. Having that little bit of extra diameter is always nice and a different tire might work better for you. The great thing about the 700c size is the endless range to try–touring, townie, and comfort bike tires and every flavor of hybrid, cyclocross, gravel, or XC tire; and usually something interesting to be found on clearance or closeout or as an odd duck in the “ridden once” basket at the local shop.

There is a difference between a setup which makes unicycling easier–and a setup which improves the technique of the rider. My attitude is that twitchier is better, because quick response provides more immediate feedback. A heavier setup, on the other hand, due to its greater inertia, masks some of the feedback.

The inertia of a heavier wheel helps to immunize the wheel against sudden, uncontrolled changes in pedaling pressure. Also, those riding without hands on the bars might prefer a heavier wheel because it is less twitchy, left to right. Beginners need to do whatever they can to build their confidence, but, IMHO, in the long run, they’ll be better off with a lighter wheel.

That’s an interesting point, I definitely have an easier time riding uphill. I feel like I can ride fastest when I am on a very sleight incline. I’ve been working more lately on my control going downhill and am making progress. Trying not to use my brake and focusing on relaxing my body while going downhill helps.

Morning Folks,

Thanks to all for taking the time to provide thoughts and feedback as to why my uni feels twitchy. I got a lot more input than expected, which is great.

Mike, thanks for the general ridding tips. One of the issues that I have is that I’ve learnt to ride a uni with Youtube and not much else. I don’t know anybody else at this end who rides. The dance floor effect / analogy makes perfect sense.

So it looks like it’s either low tyre mass, tyre type or lack of time in the saddle or a combination.

A friend is going to lend me a heavy-ish MTB tyre and inner tube. It will be interesting to see what difference it makes. I’ll also start to spend more time with surface and speed variation.

I’ll let people know how I get on over the next couple of weeks.

I’m surprised it hasn’t been mentioned, but the first thing I thought of in regard of twitchiness was to lower your air pressure. It will make it more sluggish, and with a longer contact patch, more directionally stable.

Unless I missed it, the type of riding surface wasn’t mentioned (I think everyone is assuming smooth paved road surface). The reason I mention this is because every once in a while I ride over non-paved, hard-packed decomposed-granite-type surfaces with my 32" road tire, and it definitely feels “twitchy” and not-very-surefooted. The tire transfers the feeling of less traction, and it’s not one I particularly like. Contrast this with my muni tire on a similar hard-packed off-road trail, and thngs are wonderful. The tire definitely makes a big difference in ride feel.
I agree that if you lower your air pressure, it will probably feel more stable.
Cheers! :slight_smile:

+1 this would definitely be the first thing to try, cheapest option by far :slight_smile:

And it will also make turning harder. :smiley:

All sounds like too much weight on the pedals, especially with a road 29". It’s not a criticism, I did that for a long time because all my early riding was done on dirt tracks on a muni. Being on hard tarmac pushed me to retrain myself, and it’s still a work in progress.

Mhm I have it the other way around. I sit quite well on the seat, which easily makes me UPD when riding off-road. They recently started driving with big tractors on my dirtroad, which made it quite bumpy. When I start going too fast, the uni becomes a pogostick, so I’m forced to stand more on the pedals and use my feet and legs as shock absorbers. Quite tiring :slight_smile:

The ‘skittish’ feeling is because you are undergeared. You have little resistance when you pedal.

Try shorter cranks.

As a result of this discussion, and this post in particular, I raised the seat on my 29 road uni by about 30mm.

It had already gotten harder to mount when I downsized its cranks to 110mm, and now with the seat so high, I struggle to get on the damn thing. It is nice once I’m up there, though, a HUGE improvement, but mounting has never been a problem for me before, except when I was a total beginner, so I’m not used to all the public embarrassment. The free pedal also has the annoying habit of rotating and then coming to a stop when it’s exactly perpendicular to the position my foot will be in when I try to step onto it. For a rollback mount, this wouldn’t matter, but rollbacks are not so easy with these shorter cranks, and rollback mounts are sort of a bad habit for other reasons too. Oh well, I’ll adjust to this, but if anyone has any additional suggestions…

Wow, that’s a lot. I assume, when you went down to 110mm cranks, you raised the seat an amount equal to the change in crank length…prior to raising it the 30mm mentioned above.

The gradual raising of my own seat, on all my unicycles, resulted from a combination of factors: My foot position moved closer to the toe. I learned SIF and could have all the clearance I needed for technical stuff without lowering the seat. I started putting both hands on the bars, and the added stability allowed me to drop my leg at the hip, increasing my effective inseam. Every time I experimented and raised the seat a tiny bit, I was not exactly happy about it, but later on, when I tried lowering the seat a bit, I was definitely unhappy about that.