I needed to upgrade my 20" Chinese practice cycle with a new frame, as the old one was flexing far too much.
The old 20" wheel was used in the 24" club frame first, to make sure the new frame would work.
The black frame / white wheel / white saddled unicycle is the offending article.
The frame needed to take the 20" wheel, my spare 24" wheel, and use the 22mm seat post if possible - so the obvious choice was the Nimbus-X 24".
http://www.unicycle.uk.com/unicycle-parts/frames/24-nimbus-x-unicycle-frame-chrome-170mm-40mm.html
I called in to UDC (UK) with the old bits, and Roger made sure the hub, spokes, and rim were servicable.
The Nimbus-X frame works with the 20" wheel, the original 24x 1.95 club wheel, and will easily accept a 2.5 tyre between the 70mm forks.
If you have a 20" Chinese wheel on a rubbish frame - this is a direct replacement and upgrade.
40mm machined bearing housings / with a 22.2mm seat post fitting.
