Big Man, Tiny Uni


I’ve got a 2008 Kris Holm 20" Trials unicycle. The trails near me are very technical with roots and rocks, and I’d like to take my 20" on them. Unfortunately I am quite tall and even with the seatpost fully extended my leg is nowhere near fully-extended (would like about 4" more seat height), making riding uphill or distance too difficult. There are two solutions, as I see it:

  1. Replace the regular frame with a longneck frame.
  2. Replace the regular frame with a 24" muni frame.

Getting a longer seatpost isn’t much of an option as it doesn’t seem like there are any options that would yield something long enough (even a 410mm bike post + adapter comes up short). A Nimbus muni frame + post is about $75, while the longneck frame is $200, so the muni frame seems the better option, but I’m new and am not sure if there are any reasons why that wouldn’t work.

Thanks for reading and any suggestions.

If your goal is to ride MUni on technical terrain, you definitely want to get a 24" MUni, anyway; I wouldn’t bother swapping the frame out. Keep the 20" for trials, where a really low seat is basically fine.

Heh, I have a 24" muni. But I often ride with a partner who doesn’t have a unicycle and would like the option of using the 20" as a muni as well. With the suggestion of avoiding muni on the 20", are you speaking of experience? :slight_smile: I haven’t tried it, so if you have input there, please share.

If you’re used to riding the technical trails on your 24", and if you’re like me, you’ll hate the 20". The small wheel tends to get stuck in every notch and bump (partially through not being used to it) and the long cranks put your feet closer to the ground, making for more pedal strikes.

Not that 19/20" unicycles don’t work on trails. We’ve had people on those little wheels on every long ride at every MUni Weekend in CA. Generally they’re ridden by kids who are too small for bigger unicycles, and people who do the rides so they can play on all the rocks and other challenges along the way.

It might also work if your companion on the trail is a hiker, but you’ll still tend to be faster, at least on the non-technical parts.

Well, a 20" works for MUni, basically, but it’s not as good an experience. It’s harder to roll over anything, you get more pedal hits, the trials tires don’t get great traction, and it takes forever to get anywhere. Unless you’re doing mostly natural trials type riding, a 20" will wind up being frustrating. But you can do it.

Your seat is actually to high

I used to ride all my unis with the seat so high my leg was almost straight. I still have the 36 that way.

One of the first trials skills I had to learn was riding with the seat low. It is very annoying at first, but it gets better. Look at the legs of the good trials riders in the vids, they are very bent unless the rider is standing.

So learn to ride with a low seat, holding it with one hand, then learn to ride standing just on the pedals, and to transition from riding to standing and hopping, and back. See how much easier it is to hop with a low seat ? I can’t ride SIF (seat in front) yet, but obviously I can’t learn it if my seat is to high to be able to move it to the front.

That settled, I agree with what everyone says about the muni being easier and faster. I think you could still have a lot of fun riding in most of the same areas, just don’t expect to win any races.

if you do Muni on a 20 definitely keep speed low and in control, i found out the hard way and now ive got 3 months in a cast and a ruined summer holiday to look forward to.

I took my 20" on a trail that was sort of steep and a little rocky (not real technical). It was fun for a little while but I was more than happy to trade it for the 24".

I ride my 20" on trails sometimes and I have to say you’ll most definately enjoy riding on your 24" more. You can just wait for your riding partner to catch up when they get behind.:wink:


Unfortunately, I’m going to do so with absolutely no data whatsoever, basing my opinions on speculation alone.

Since it’s clear you’re looking for a solution for your 20" problem while the 24" is being lent away and because it seems you also have financial motivations… I will suggest Option 2, replace the current shorty with a longer 24" frame (compatibility permitting). Otherwise, if you want to be a Lowwww-Riiiiderrr as feel_the_light suggested, you could try the bike seatpost + adapter option. This also would appeal to the pocketbook, methinks.

Good luck, and post whatever MacGyver solution you devise.

The disadvantage with option 1 is it costs more.
There are a few disadvantages with option 2. Your frame will be heavier, which makes jumping a little harder. A large frame on a small wheel doesn’t look as aesthetically pleasing and also makes certain tricks harder/impossible to do. Any trick that requires you to rest your foot on the frame is going to be harder with a 24" frame fitted to a 20" wheel. Eg one foot riding, wheel walk, gliding, coasting, stand up wheel walk. If you don’t think you’ll ever want to learn these tricks then using a 24" frame will present no problems. You then need to decide whether it is worth shelling out extra money for a KH long neck which will look nicer and weigh less.

I suggest a 3rd option you might like to consider:
3. Replace the regular frame with a Nimbus street longneck frame and a compatible 2.2mm post:

The Nimbus street frame is only $68 but you will also need a good quality 22.2mm post. UDC in the US only stock this cheapie:

It does come in 500mm lengths so you’ll have plenty of height. If you end up breaking your post it may be hard to track down a strong replacement. The best quality 22.2mm post I know of is the primo “the rod” post, but you’ll need a rail adapter to use this as it is a bike post. There is also an alloy Nimbus post in 22.2mm if you manage to track down one of those.

This option will come in somewhere between 1 and 2. The street frame isn’t going to be as light as a KH but it should be nice and strong plus it gets you the height you need.

That is a great suggestion as well :), my only question is whether a Maxxis Creepy Crawler or other 2.5 inch trials tire will fit in the freestyle frame.

The Nimbus X Street frame is designed to fit trials tyres. Its the frame found on this complete unicycle.