Upgrading a Nimbus Trials

I’ll try and answer as many of your questions as I can:

There is a uni hanging up in my shed with a Kris Holm Splined Hub fitted to a Nimbus II frame. It’s been that way for the last two years. I’ve probably ridden hundreds of miles and dropped cumulatively hundreds of feet in that time on it without any problems. It fits. Having said that you do need to just push the bearings in a little harder than you would with 40mm bearings, and also pull the legs out very slightly. The same goes for the Onza and KH/Onza hubs.

Hub Comparison:
KH - a little heavier than the others, no problems with the hub but the cranks can twist as they are a non-circular cross section.

Onza - lighter than the Kh, the cranks were good but there is a problem with the way the hub fixes to the axle, this can become apparent in quite a number of the hubs produced but can be fixed with some superglue very satisfactorily.

KH/Onza - the strong hub design of the Kh with the strong crank design of the Onza plus a fancy taper widget so they don’t creak when you ride. The lightest splined hub on the market.

All the splined trials unis on the market currently are pretty good, the more you pay the lighter and stronger uni you get, but there’s not that much difference across the board. I’ve ridden all four that you mentioned, the KH and Koxx are a little lighter than the other two but it’s not a big difference, especially considering the extra money that they cost. There are a lot of serious trials riders perfectly happy jumping around on the £175 Qu-Ax. I hope all this is helping you rather than just getting you more confused.

I think you would be okay with even the cheapest splined crank/hub set. You really don’t need the best out there, just as long as it’s splined you would have to go to a lot of truoble to break it.
As long as your not doing huge drops, (5-6+ feet ?) and you land properly, any splined hub will hold up.

But square taper hub and cranks will not.


Thanks loads guys! Especially forrestunifreak and kington99!

I’m gonna go for the KH splinted crank+hub set then do more drops without the fear of smashing my face against the pavement! I suppose I should get a helmet aswell. And leg pads and gloves and arm pads aswell… It never ends!

kington99- It’s nice to know that someone else has done the same thing as I will relief. I will bear your advice in mind (push the bearings in a little harder than you would with 40mm bearings and pull the legs slightly). I can’t wait!!!

Comparing the Onza Trials and the Nimbus Trials Unicycle-

They have the same:
Tyre (don’t know for sure but looks identical!)

And the seatpost for the Onza is only 1.8mm more in diameter. (and the Nimbus is lighter).

Except for the hub/cranks they’re basically the same unicycle! Can’t wait to get a HK hub! I will practically have an Onza unicycle, with more personality!

It is depressing also, that instead of buying a Nimbus then having to spend £80 on new a hub, I could’ve bought a Koxx Devil for almost the same price. I suppose that’s the way it goes. Why Yoggi why?!

Thanks again.

The Onza trials has a CroMo frame which along with the splined cranks is probably why it weighs more than the Nimbus trials