Coker handle: is this draft stupid?

Still two month to go before riding a Uni…
so I was making sketches about my dream Uni
part of this crazy design was about a handle…
may be this design is a bit unrealistic …
so I tried to draft the same handle design for a Coker
here it is.

this (big) handle is built on an axle in front of the wheel
may be one could imagine a way to block the handle
when one does not want it to rotate aroud it’s axle…

why this?
it is supposed to help climb steep decline while standing on
the pedals and having the saddle slightly tilted backwards.
moreover it is supposed to help when dealing with handling
twists with the big inertia of the wheel…

well just supposed…

your feedback?

(sorry the image is not clear: it has been copied from a Frame original)

It’s very large. I wouldn’t want that between my legs if I were to crash.

sure that’s why when you lose your grip on the handle
the handle is free to rotate…
(and bounce back… and hurt you ;))


don’t make one thinking I’m gonna order it!

Re: Coker handle: is this draft stupid?

This is true for bicycling where you are already bent over and have handlebars to work against. By shifting back on the saddle in a climb you maximize the larger muscle groups.

I think in unicycling the power position is when your back/pelvis is as straight as possible. You need to get as much weight as possible directly over the dowward pedal and if you are using a handle the downward force is maximized. I find bending forward less efficient.

seems a little big i can’t see it working that well

There are two ways to use a handle to help to achieve maximum torque: sitting on the seat and pulling up; and standing on the pedals and pulling up.

For both of these functions, you need to be able to apply maximum upward force to the handle. You are effectivwely pulling yourself down onto the pedal.

If you are pulling up on the handle, the muscle action relating to the pulling up is similar to the muscle action you would use if lifting a very heavy single-handed dumb bell, or a bucket of water: you want to keep your hand (and the centre of mass of the weight you are lifting) close to your body.

For this purpose, a handle that is just in front of your crotch is about right. A good place to mount such a handle is, er… on the front of your seat.

If you do more standing up than sitting down, there is an argument for having a handle which is a bit further forward, so that you can allow the seat to fall back a little way so it isn’t in the way. However, it is not a good argument, because the pressure of the sides of the seat against the insides of your thighs helps with steering, balance, and general ‘feedback’ from the unicycle.

If the handle was so far in front of the seat that when you held it in the right position for maximum torque, the seat was way back out of the way, then you would need to divert effort and skill into maintaining the lateral stability of the unicycle - a bit like when you’re riding seat out in front.

So, for maximum torque, the handle should definitely be just a short distance in front of the seat.

How should it get there? Bolting it to the seat seams obvious. A stronger structure could be made by attaching it to a lower point and triangulating it, but at the expense of additional weight.

Of course, you don’t always use a handle for maximum torque. On rough or difficult patches, a light touch on the handle gives an increased feel for what the wheel is doing. It gives you that edge when coping with a series of unseen or difficult to read hazards. The ideal position for a handle doing this is also just in front of the seat because you need small movements of the handle to give you the feedback (a longer handle will move further) and you may need to stand up suddenly to apply torque.

So that leaves only the option of a handle for supporting the rider’s upper body when (s)he is riding long distance and needs streamlining - or simply to take some weight off the posterior.

Such a handle will only need to take a small amount of weight, although it will need to be robust in the event of a crash. A handle mounted on or just below the seat seems the best answer. This offers the shortest route from the uni to the handle, so lightest weight.

A handle up there in front like a set of bicycle bars would be no use at all for any of the things that you use a unicycle handle for.

Also, you will normally need a single handle, not a double one. especially when working hard up or down hill, you need one hand free for balance.

So, nice try but no cigar. Nevertheless, it is good to explore these ideas. A good rule for such explorations is keep it simple. The current design (Reeder handle or similar) is simple.

Is the only brake handle available a b*ke brake? I had some ideas for a more natural design for a uni brake handle that would be easier to grip. The only problem for me though is figuring out how to get the old handle off and the new one on. Any ideas?

I’m still trying to figure out the purpose of this handle design. All I see is a lot of extra material and extra weight. This extra weight will make the unicycle a pain to mount and handle.

On a Coker, you can have a handle that extends much farther forward, to lean on like a triathlon bar. This would be good for road riding, but work against you for tight turns and other types of riding.

When riding uphill, your center of mass has to be in the same place, in front of the wheel axle, no matter what your handle is shaped like.


At least you have the initiative to go to the drawing board. Your first draft is perhaps a bit excessive though.

I favor the wyganowski ext bar with the addition of an aero bar wrapped with spongy tape. (hope the picture attached)

I like the handle to be higher than the seat. The reason for this is that I think it offers better leverage at Coker speeds. If my hand or hands are between my legs and I hit a pothole or bump, it is like trying to run with my hands in my pants. Having a grip a little higher, like at the solar plexus, has saved me from many UPD’s.

I believe that future touring seats will incorporate a handle system. An adjustable handle (height & tilt) would be perfect.

Until then, stick with what works.

resized photo:

thanks Sofa


thanks all for your remarks
when looking for something I usually follow unusual paths
rather complicated design pop up first
then by simplification I want to end up
with “simple” (though “simple” is not simply obvious).

particular thanks to Mikefule who went to the point:
as I have said this was not initially thought for a Coker
and things evolved from a remark: when jumping people usually
have their seat in front of them… I was wondering if the other
way (seat behind you) could be done by having a handle in front of
you that you pulled and thus the seat will lean backwards.
the question is : where to fix such a handle? … not on the seatpost!
(so here I’d love to challenge the general assertion that it should be fixed here)

as Mikefule pointed out the Big flaw was that the force had to go
down, not in front of you!
does that means that a design with a frame tilted forward
would make sense? (when standing you will be in the axle of the frame
when seated the axle will be in front of you)?
with this in mind I asked john Foss “does the axle of the frame has to be aligned with the seat” I think he answered no.

the other point is this: when seated will a handle not operating
on your axle but in front of you be of any help to correct
slight twists?

so does this nonsense makes sense?


It might work better if the red bar is shorter, like maybe only a few inches long. The long red bar is going to cause funny leverage effects when you pull up or push down on the handle. It will have a tendency to push or pull the unicycle off balance in the forwards or backwards direction.

Something I noticed with my Coker handle is that the further out I put the handle the less weight I am able to put on the handle. I want to be able to press down on the handle to relieve pressure on my crotch. But when the handle is out far I cannot put much weight at all on the handle (and thus relieve pressure on my crotch) because there is too much leverage pushing the unicycle forwards and off balance. Moving the handle closer to the seat makes it easier to put more weight on the handle. You’ll want to keep the red bar as short as possible to minimize the leverage effects when pushing down on the handlebar.

It sounds like you have a pivot or hinge where the aqua bar joins the red bar. That’s going to be interesting. It will allow you to put the handle right into your gut and push down. That would allow you to get some weight off your crotch. Interesting idea. It may cause some problems though because when you hit an unexpected bump you want to be able to push or pull on the handle to regain balance. You won’t be able to do that with the hinged handle. It might make it more difficult to recover from bumps.

I like the ideas though. A bit of thinking outside the box. Lars Clausen has an interesting handlebar setup that is unlike anything I’d seen before. That setup allows him to push down and get weight off his crotch. I can see the advantages of his setup.

I like seeing new ideas for handlebars. The new designs give me ideas as I work on future versions of my handlebar setup. For example, after seeing your idea I can see putting a pivoting aerobar setup on mine. I don’t know if I’ll do it and I don’t know how well it would work. But I can see how it could be done. I wouldn’t have thought of that had I not seen your design.

What I like about my JC Coker Handle is that it is modular. It is easy to add new handle designs on the boom and position things in different places. It’s quite the setup for experimenting.

What would be cool is to figure out a way to add some Lars style handlebars. I think that style of handlebar has potential.

Now that I think about it, I have seen handlebars similar to Lars’ before. Look at the picture of Keith Cash on his cross-country ride.

Re: thanks

There are three relevant points: the axle of the wheel, the centre of mass of the rider, and your grip on the handle.

If you are sitting on the seat, then that is a fourth point.

Now your question relates to the relative positions of the first three. It really doesn’t matter what shape the handle is, or where it’s attached. It could be attached to the top of the seat tube, the front of the seat, or come off the back of the fork crown and go in a big swirly loop over your head - it wouldn’t matter. Well, it would, because it would be heavier, and introduce more flexibility, and these would both be bad things.

The height of the handle relative to the axle IS important. The fore-aft rake will naturally adjust to the best position anyway. If, in doing so, it pushes the seat too far back, that is a bad thing.

But you gain NOTHING from attaching the handle to a different part of the unicycle.

This reminds me of the old idea for curved cranks on bicycles. the idea was that when the crank was pointing upwards, the pedal was already past top dead centre… The effect is illusory.