Because I love ridiculous builds, it will be give a disk brake and used for muni (small stuff)
Iām testing a theory that with a good brake, and riding short (75-100) cranks that are on my other unis it will control well downhill. The 4" tire rolls over everything, and the smaller wheel with tiny cranks means I can get a high cadence to ride through obstacles easy.
Itās hard to believe that a 20" x4" tire is even a thing. Who makes your tire?
Vee make such tyres. They make them for a few cargo bikes, kids fatbikes and also a handful of ebikes. I see a few such bikes here in Norway. Indeed one of my colleagues has one.
You can find a few 20x4 tyres here, though there are more than this
A lot of ebikes run fat 20" tires so thereās a few different manufacturers. You can get a few different tread patterns too. All of them are made well, but itās difficult to find one thatās light weight.
I shall assume this is the tyre you have on it now?
FWIW the Mini Hatchet also has a tyre of that size and before that the Nimbus Purple monster.
[@Bug72 You even commented in that thread! 
]
Though that URC frame that @Sexy has would actually be a better option for an adult as discussed in the Mini Hatchet thread.
P.S. I actually have the same frame in the same colour myself (wellā¦ it is technically my daughterās butā¦). I have yet to put a fat tyre on it. Perhaps I should? 
Check the rim Marco is selling. Itās a bit thinner from a true fat tire rim (Iād have to double check but itās like 30-40 ID vs 60-80 for a 26" one.
The tire is still pretty wide though and Iām not expecting and trouble riding off road with it.
Took it for a ride to work yesterday and it can actually get some good speed on it, not as fast as my 26 or 29, but it was comparable to a 24" Iād say
In some ways that sort of makes sense. While the big tyre will be heavy, on such a small wheel it probably isnāt too bad, all things considered and the outer diameter must be getting close in size to a 24 anyway. In addition, you have such short cranks.
Might actually work quite well as a travel unicycle. I mean if you took it apart and deflated the tire I presume you could get it in a regular suitcase. 
Yeah, I had a 24" sold recently that was supposed to work for this but a 20" can fit diagonally in a carry on.
Though it is a 20" I find a fat tire is a good cheat code for traction, but have also had what Iād call similar results with a 2.8" as well. So if I do travel with it, Iāll probably look at a smaller tire.
I just have winter trails near me that require a 4" tire to ride and this will def be a work out
Today I picked up this beauty from FB Marketplace. The seller had the age old story of having bought it but never learnt to ride it, so to my benefit she was selling it way too cheap because she didnāt really know what she had. I paid R800 (or Ā£33 at todayās exchange rate), which is a bit of a bargain.
Itās set up incorrectly, and Iāll sort that shortly, but for now Iām just chuffed to have a 24" in my collection.
This is my eighth unicycle.
A good catch - my 24" is my most used uni - itās such a useful size - you can get up to a fairly good speed (especially with shorter cranks), but also carry or push it into a shop with no complaints.
Are those ISIS or cotterless hub + cranks?
My latest unicycle purchase Iām not really counting as a whole unicycle since Iāve not even reassembled it since it was delivered (and Iām supposed to be slimming down to just two unis for a downsizing house move). However I spotted someone selling a 48 hole ISIS hubbed rusty 20" for just Ā£10 in London, and persuaded them to post it to Derbyshire. So once Iāve moved Iām hopefully going to upgrade my original cotterless 24" to ISIS (I have an old frame with 42mm bearing housings that I can use).
That Nimbus is a bargain just for the ISIS hub (Iām guessing thatās the source of your thread about swapping out cotterless for ISIS?).
My daily ride is my 26er which I love, but have wanted to try a 24" for a while, so when this one popped up, I had to get it. Part of my plan with it is to pack it into our luggage for use in Blighty later this year, but Iāll have to see how the wife feels about thatā¦
It also has cotterless cranks, but given their condition (almost new) Iām in no rush to change them, though I intend to get shorter cranks whilst in the UK.
Thanks for your PM earlier, Iāll reply later.
You will find that cotterless cranks are just fine and they are so inexpensive you can buy all different sizes to try out for the same price as one set of good issis cranks. I have said it many times on this forum, I put more miles on my $159 used 29er UDC trainer with cotterless cranks than any other unicycle I own. May I point out trouble free miles and no crank issues. Enjoy
Youāre right of course - but my excuse when I bought my spare parts ISIS uni was that it was being sold for less than even a pair of new cotterless cranks (and I happen to have a pair of 102mm ISIS cranks which is the next size I want to start using on my 24"). However my excuse has since broken, as a pair of (bright red!) 100mm cotterless cranks came up for sale on UK ebay soon after I bought the rusty ISIS uni, and I went and bought those too. So the current plan is to do a quick crank swap to get used to the 100s with my current hub, and then rebuild the wheel as isis when I have time, after which Iāll be more confident doing muni and hopping etc on that uni. But so far (without doing much off road and not yet having mastered hopping etc) the various lengths of cotterless cranks Iāve used on my 24" have been just fine.
We had a prolonged power outage today, so I chose to use the time to clean up the 24" Qu-Ax I picked up the other day.
Firstly, I put on a longer seat post and made sure both the seat, and the wheel were facing forwards.
Next up, I broke out some metal polish to have a go at the cranks, and Iām very happy with the results. Finally, I used some engine de-greaser to clean the wheel.
Isnāt the new seat post facing backwards? As far as I remember, the reinforcement should be at the front.
Iāve seen some discussion previously on this, and came to the conclusion that it makes no difference.
So for those who see my posts about my 29", youāll know I love tiny cranks. I run 75mm on my 26", 100/75 on my 29", and recently I got a new 20" from Mad4one and put a set of 75mm cranks on it after selling a 24" wheel.
It currently is equipped with a 203mm rotor, basic dual piston Shimano brake, and a 2.4" Maxis DHF.
It was originally intended to be used for Muni (downhill specifically), but has started to be used as my around town uni. My 29" isnāt the best in winter conditions with snow so this was intended to help me practice riding above my usual 120rpm.
Well turns out if you spin fast enough you can get a 20" going 15kmh average. Iām calculating that Iām up to about 180-240 rpm now and have been loving this for transportation. Itās smaller and more easily transportable than my 26" but still of a good speed for getting around town.
I never though Iād be going back to a 20" after my learner but this has been a really fun uni to play around on.
Part of me loves when a stupid build comes together, and this is by far one of the best pay offs.
My only gripe is the paint Marco and the team used isnāt the most durable, but besides that the uni has been riding pretty well.
Planned upgrades are a new purple BMX rim to shave 200g off the rim and replace the fat tire tube that came with it. 20" fat tires are fun but I find the 2.4" at lower pressure rides really stable even in bad conditions.
Are your knees still okay?
Yeah, Iām used to the smaller cranks and exclusively ride them for a few years now. Itās partly why the saddle is so high but Iāve developed some good muscle power for the smaller rotation.
Foot placement on the pedals and knee alignment is very important but you find the ways to make it work.
