I am the proud owner of a nimbus 24" muni and want to start doing some trials, do you think it is worth me getting a trials unicycle as well or not. Is there that much difference between a 20 and 24".
I was thinking of getting a KH20 2007 edition for £250 if I were to get a trials.
I have only been unicycling about 4 months or so.
Thanks!
This is a unicycle forum. The obvious answer around here is “Yes”. However, that is a decision you should make by yourself. Borrow a 20-inch uni and see if you like it.
I learnt to ride on a 20" and find it easier to hop etc. as opposed to my 24 as the seat can go lower.
I was wondering if there is a big difference between them when doing trials.
One way to help you decide is to keep doing Trials on your 24". When you get to the point where you think the unicycle is holding you back from getting height or other limitations, time to invest in the next unicycle… 
Great answer. I am already really poor from getting my nimbus (from a cheap ebay uni) and in the next few months I wan’t to get a coker which will cost me another £200. i plan to do the London to Brighton cycle race with my friend next year which is 56 miles and I need to have money to buy one.
Thanks!
Hmm. Does anyone do trials on an ultimate wheel?
One would save the weight of the frame, the seat, and the post, plus there’s no seat to get in the way. I suppose there’s also no handle to grab when jumping, but one could just grab the tire in that case, right? 
LOL I have never ridden an ultimate wheel. It’s on my list of things to do. I dunno maybe in theory it would be easier in many ways. But also harder in others.
The difference between a 20 and a 24 is massive. 24 is 20% (a fifth) more than 20. That’s a fifth more diameter; a fifth more weight in the rim and tyre (all other things being equal); a fifth more distance travelled per pedal stroke; a fifth more leverage to fight when controlling the uni; a fifth more radius to the curve when you turn without scrubbing the tyre.
Add to that that a MUni tyre is probably bigger than a true 24, and built heavy (grip, puncture resistance) and it is clearly the right tool for Muni, and not much else.
I probably do more rides on my 24 than any other, and when I get on the 20, it feels like a toy.
The difference between a 20 and a 24 is more than the difference between a 24 and a 26, or a 26 and a 29.
If you really want to get good at trials you will have to get a 20". As Mike says, the difference between the 20 and the 24 is massive. You can maneuver a 20" round obstacles way easier than a 24.
I have both, and despite being expensive to buy (Although, try buying a top of the range bike!) to start with ,its great having the right tool for the job.
Since you’re writing the prices in pounds, im guessing you’re from the UK? Theres a UK Forum if you are interested. Check us out! www.unicycle.org.uk/forum
Edd
Unless you’re doing “Ultimate Trials”. In that case, grabbing the tire would be like a dab. 
Go to a unicycle hockey practice in Hackney or Horsham (Westway in Shepherds Bush is temporarily suspended) and you’ll be able to borrow one to try out. that’ll help your descision but you may want to hold off until after you get a 36"… you’ll probably find that you want both!!