acceleration unicycle

Hi all,

I’d like to ride long distances, over hills and colls…

My question: is it possible to get this

(I don’t know the word in English :wink: )

on a unicycle?

Janklaas Claeys,

I don’t know of any unicycles with ‘derailleurs’. The problem is that on a unicycle you need to be able to put pressure backwards to correct your balance and even without a freewheel mechanism you have to keep the chain tight so it doesn’t slip on the chainrings. Well that’s my understanding anyway.

Do a little search (click on ‘search’ at the top right of the page) for ‘uni.5’ or ‘geared hub’ or ‘schlumph’ for info about alternatives.


The answer to the question is “no”, but it is the wrong question!

So far there is no system for changing gear ona unicycle while you are riding it, and there are various technical reasons why it is unlikely that such a device will ever be made. There are one or two people making unicycles with 2 gears, but you have to stop and get off to change.

However, why ride a unicycle, but go to all that trouble to make it more like a bicycle? Why not ride a unicycle but add a front wheel and handlebars? :0)

The whole point of a unicycle is its simplicity, and the need to cope with the compromises. You choose a wheel size, a tyre, a set of cranks, and then make the most of the set up that you have chosen. You can choose wheels from about 16 inches to 36 inches, and cranks from about 4 inches to about 7 inches. There is a huge variety.

Then you just ride. That’s the whole point. I’ve ridden 20 miles on a 20 inch, 24 on a 24, 30+ on a 28, and 50+ on a 36 inch wheel. Some people who write in this forum ride 50 - 100 miles in a day, over mountains and cross country. Look for threads with the words ëpic"and “Coker” in them. You will be amazed and inspired.

People have ridden across America on 24 inch basic unicycles.

It sounds like you haven’t tried long distance unicycling yet, but you already want to find a way of improving it. That’s the wrong approach. Buy a 24 inch unicycle and get the miles in. It is a very special method of transport - faster than walking, slower than bicycling, more challenging than either. You get to see the scenery, the wildlife, and meet people. You get fit, you enjoy it, and you get a great feeling of achievement.

Read a few threads, look at a few galleries, and see what can be done without a derailleur! ;0)

Have you read about the adaptation of the Schlumph hub? That design allows you to change gears on the fly by kicking a little nub (much like the old KH cranks) with your ankle. I believe they’re also considering adding some sort of lever under the seat or something along those lines to their design. There’s a little bit of info on their site. I just realised I’ve been spelling it wrong…


Re: acceleration unicycle

> The whole point of a unicycle is its simplicity

[begin rant]

You unicyclists makke me sick! Simplicity? I don’t think so. Lah di
dah, look at me sitting down while I ride. On a saddle. With a
handle. And a frame with bearings, no less. Maybe even a trip

If you want to argue that simplicity is the way to go, ride an
ultimate wheel and show the rest of us the one true way (with
apologies to BC wheel purists). Otherwise, why not let people have
fun riding what they like and thinking up new challenges, whether
technical or physical.


If you want to argue that simplicity is the way to go, then walk naked and barefoot.:smiley:

I have an ultimate wheel, on which I am not particularly good.

I agree with your basic point that it’s up to each rider to choose his/her own level of simplicity or complexity. However, I do maintain that if you try to make a unicycle too much like a bicycle (shiftable gears, for example) you are in danger of missing the point. It would be like having a motorcycle with a roof, windscreen wipers and two extra wheels for stability.

not being “technical” cannot argue at that.
Ideally and topologically I bet this is possible: now if you tell
me that there is no steel that will support the stress or the friction I can’t argue.

because I need a geared-down Coker to go up steep slopes:
why? because my doctor does not want me to continue to tear my muscles apart and tear my tendons…
(I am not young any more and I failed
to notice that)

bear (again on unicycle leave because of teared tendons)

Re: acceleration unicycle

“Mikefule” <> writes:

> I agree with your basic point that it’s up to each rider to choose
> his/her own level of simplicity or complexity. However, I do maintain
> that if you try to make a unicycle too much like a bicycle (shiftable
> gears, for example) you are in danger of missing the point.

I get it, but you are missing my point. You’ve chosen a particular
level of complexity that you seem to feel represents “proper”
unicycling. Any more or less and for you the experience is
diminished. You put that forward as your idea of “the point” of
riding. That’s fine with me. More power to you.

It’s when you start telling the rest of us how to enjoy the sport that
I object. It is patently not the case that the “whole point of
unicycling is its simplicity”. For many, the point is the difficulty
yet tantalizing attainability of riding. For some, it is competition.
For a few it is realizing mechanical innovations (like shiftable
hubs). There are unicycle racers, dancers, clowns, and on and on.
I see lots of “points”, not one.

From a broader perspective, I’ve seen differing goals and technologies
as a common feature of all the outdoor sports I have participated in
through the years. Many sport climbers “miss the point” and never
seek out the adventure of traditionalist detractors, but then the old
traditionalists missed out on the transcendance of succeeding on a
route requiring absolutely every iota of gymnastic ability,
visualization, and focus that at-your-limit sport climbing requires.
The squirt boater with intimate knowledge of every eddy and underwater
current might look down at a rafter yelling “wheeeee” and at the same
time miss out on a simple part of joy of getting out to ride down the
river. And let’s not even discuss skiing vs. snowboarding!

My point is that there’s more than one way to skin a cat. If you want
to look down at attempts to build shiftable unicycles as missing the
point I’m not about to stop you, though I will tell you that you may
be the one missing a point. When you tell others there is only one
proper way to enjoy what is, after all, a contrived sport, well, then
I’ll start arguing that there’s more to the picture than what you
happen to be focused on.



The main problem with gears is play, or lash. That is, if you want to change gear, then there has to be some slack in the system to allow that to happen. If there is some slack in the system, then that causes problems with smoothness of pedalling (especially idling, or when changing speed) because the cranks will move a tiny bit before the slack is taken up. The geared systems that have been experimented with generally use “sun and planet” gears, as found in a conventional hub gear (e.g. Sturmey Archer), but selection of gears involves getting off, changing gear, then making sure everything is tight so there’s no lash in the system.

I suppose this could be overcome, but rememebr that the market would be very small indeed (a few hundred units worldwide?) so there would be massive R&D costs, and no savings on economies of scale. I think geared unicycles are doomed to be the province of the enthusiast and inventor, rather than a commercial propostition on any major scale.

But back to the original point: a Coker with 170mm cranks gives the same mechanical advantage as a bicycle with a 36 inch gear. That’s like having a mountain bike with a 1:1.38 gear ratio. Say 40 teeth at the front and 28 at the back, or 36 front, 26 back. That’s a pretty low gear.

Basically, all unicycles are in a low gear compared to any conventional bicycle. The problem with hill climbing is usually technique, stamina or over-ambition.

Given the recent auction of the 26/39er, I think several hundred units worldwide is a wildly optimistic figure.

On the subject of shifting on the fly, I think the reality is that few people could master shifting without a dismount even if the unicycles existed. For most, a mid-motion shift would meet with a swift udp or faceplant. I think the concept is overrated.

Sounds like you are pushing too hard. With improvements in technique it will probably be possible for you to learn to ride steeper climbs without damage. But of course you will have to be very careful working at it. There’s a big difference between a pedaling technique where you push down super hard, and one where you make strong, smooth circles with your feet.

For health reasons, I’d suggest a smaller wheel for the rides with steep climbs. Like a 28" or 29", which would be much lighter than the Coker, and hence easier on the muscles and tendons.

A shiftable hub would be much more expensive than most of us are willing to invest, and it might be easier to just walk up the hill… :slight_smile:

Does gear inch on a bike actually take into account crank length? I thought it was just based on the rollout of the bike in that gear being equal to a certain circumference of larger wheel.

If that’s the case, a Coker with any size cranks is a 36 in gear, but that doesn’t mean much if you want to talk about crank length.

The gearing problem for unicycles has been solved. But there is not enough market demand for the hubs to be worth manufacturing. A shiftable geared hub would have a similar problem, only it would be less worth manufacturing.

This doesn’t mean the inventors out there shouldn’t build prototypes and develop the concept. I want to try one!

Meanwhile, there are always cruder ways to get gearing. The simplest is with a chain drive. If you don’t want your unicycle to be tall, you can use and inner and outer hub setup to gear the wheel on its own axle. This is going to add some weight and some friction in the drivetrain, but I’ve ridden a working one (in 1982). But it wasn’t shiftable.

Yes and no. I specifically referred to mechanical advantage, and in doing so I made a rather sweeping assumption that most bicycles have 170 mm cranks (or as near as makes no odds).

Describing bicycle gears in inches arose from the need to compare modern “safety” bicycles with penny farthing “ordinary” bicycles. In the days of the penny farthing, the macho factor was wheel diameter, and the general perception was that big wheel = fast. (I cannot recall ever reading of great attention being paid to crank length.)

The idea is that if you gear up on a 2:1 ratio (e.g. 48t front, 24t rear) and have a 26 inch wheel, that is in some sense “equivalent” to a 52 inch wheel (48/24 X 26 = 52).

However, it is not enough to say that a Coker is a 36 inch wheel and is therefore “equivalent” to a bicycle with a 36 inch wheel because unicyclists are much more adventurous with their crank lengths. A Coker with shorter cranks may be faster on the flat, but it requires more pressure on the pedals to get it up hills - which is what prompted the discussion. (Not teaching John to suck eggs, but explaining for those who are less familiar with the principles.)

So the point I was trying to make was that a Coker with the same sized cranks as a bicycle should be no harder to pedal up hill than a bicycle with a 36 inch gear (ceteris paribus).

In practice, ceteris aren’t paribus, of course. Bicycles are nasty heavy things with inefficient chain drive. And every skoolboy kno that short wheel bases are good for hill climbing.:wink:

Uh, so how do I get the stuff to come out of this here egg?


Anyway, yes a Coker is roughly equivalent to a bike with a 36 inch gear. The “roughly” part is where you account for different cycle weights, drive system friction, and crank length. Hmmm. That’s a huge amount of wiggle room for us nerds here in the newsgroup. Oh well, you’re not going to get an exact comparison between a uni and a bike anyway.

Here’s one: a unicycle has half as many wheels as a bicycle.

How exact were you hoping for?:smiley:

I did say nerds, right?

Maybe I should have said super-geeks. Not sure what works best for the UK… :stuck_out_tongue:

For geeky example, the bike also has more frame, a drivetrain, handlebars, etc. Take away the extra wheel and you have all that extra hardware.