Geared Unicycle Blog Post: three basic designs

I have a blog which mostly covers tech subjects but today, because I recently purchased Pete Perron’s Red Menace, I did a blog post on geared unicycles. I realized that I am lucky to have in my position one of each of the three main categories of geared unicycles, so I wrote about them.

Anyway, the post is here:

Comments? Put them on the blog, or here.

Very Interesting reading Bruce.

Thanks for sharing :slight_smile:

Very good write-up…thanks

Well done.

Thanks!

Has anybody tried Huni-Rex? It’s a chain-drive variation – separate chain drives on each side.

http://www.huni-rex.com/index.php/en/component/xvs/?controller=termek&cond_kategoria_id=1&termek_id=14

I feel like I need one in order to complete my collection…

Currently available on Recent thread. Kind of an inverted penguin. Thanks for your well-informed blog post!

Yes… I have tried one… its horrible!!!

Holy pedal strike, Batman!

Good golly, Bruce! You gotta share your toys.

Nice write-up, I’d love to try them sometime. The jetpack too. :slight_smile:

Nice job, the reference to Lance is may be old fashion now …

We had a huni-rex at club to try out. Takes a bt of getting use to, great on the flat and easy to ride fast, watch out for pedal strike on sharp corners, we had one of our riders leave some arm on the pavement. I have worked out it it would take a person with super leg muscles to ride it up a hill. Very differcult to get the chain tension exactly the same on both sides so the slop tends to be one one side and not the other, but you do get use to it.

enjoy picture of how to get Huni into other gear…WALK IT

walk it.png

Close up of frame, very nice

huni1.jpg

Thats me holding the Huni-Rex in the second of Pagee’s photos. It was also my elbow that lost some skin from a huni-rex mishap. I’m going to try out shorter cranks than the current 125mm Ventures to try and reduce pedal strikes.

I think that the Huni-Rex could be mightily improved by inverting the jackshaft such that the pedals sit above, rather than below, the centre of the wheel, thereby eliminating pedal strike. Either that or make a 29" or 36" version.

Do you think that it would work well with the pedals in front of, or behind, the hub? That would solve the pedal strike issue, but avoid the extra height that would come from having them above (which would be less desirable in the event of UPDs)

Yup, pedals in front, might even ride better, but with that existing design I would not ride at speed unless the course was very straight.

I can remember having some high speed pedal strikes on my BMX bike as a kid, they were not happy making :astonished:

I think having the pedals a bit higher is actually better in the event of a UPD. I find myself a bit too close to the ground when riding a geared 29" – I quite like the pedal height of a 36". If you are too close to the ground then I think it might be harder to get your feet ready for landing, thus making the UPD worse.

So, I think I’d be happier with the Huni-Rex if the pedals were above. It would make the frame larger and less portable, but it would make for a very strong frame, and a comfortable height. It would still be missing the best feature of Red Menace which is the ability to change the gear ratios.

But, I’m not sure about the pedal height. I try to avoid UPDs, not do scientific research on them.

I’d prefer my pedals lower in the event of a UPD- obviously not so low that pedal strikes are an issue, as they are with the current location of the pedals beneath the axle. So I’d probably want them level with the axle which would require them either in front, or behind, the axle- not sure if that would create difficulties when riding.

Trying to stand up with the pedals in front or behind the axle would certainly create “difficulties”.

Would it? Why?

I’m not saying it definitly wouldn’t, but I don’t think it’s something you can just state as a fact- a bit of reasoning is necessary to back up your opinion.

And, I am an experienced unicyclist- my instinctive feelings on it are that having the pedals a few inches front/back of the axle wouldn’t create any instability that couldn’t easily be compensated for by a slight lean.

Seems to me it would. There’s an inherent difference between a verticle line down from your CG through the pedals and axle, vs not. I’m no physicist so can’t really expain it well, but in my experience gravity works, and it works straight down. If you stood up on pedals that are not in that straight verticle line, it would tend to rotate the pedals down below the axle until gravity had acquired equilibrium again. You might be able to keep things upright by holding the handle, but there would still be an issue.