Munimanpete - it is indeed true you can build yourself a kick-ass trials uni with a Nimbus Trials 20" and an Onza hub. It will be lighter than the KH20 and functionally just as strong a uni. You won’t have the larger 27.2mm seatpost, but that’s a small sacrifice, IMO. In terms of clearance both the KH20 and the Nimbus II frames will be OK. If it’s so muddy that the frame is getting jammed up with mud, odds are that conditions will be so slippery that you won’t be able to ride anyway!
Wheelbuilding will cost you around $50 to $80, depending on yr bike shop. A lot of bike shops have a policy of using new spokes to do rebuilds, and at $1 per spoke this adds $36 to the rebuild price. However, if the wheel to be rebuilt is brand new, and the difference in spoke length is only 0.5mm as Pete indicated you may be able to get away with using the original spokes.
I hope this helps with your decision.
T()ny
www.unicycle.co.nz
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