Building a 36" Ultimate Wheel

I have a 24" Nimbus Ultimate Wheel, but wanted to have a 36" one. Modeled after the wrinkles of drag racing car tire, the spokes are laser cut from 6061 aluminum rectangular tubing. To overbuild, both hub (also laser cut 6061) and spokes have a wall thickness of 1/8". The rim is donated from a Coker wheel.

I originally tried to hire a welder to weld them together for me but after two welders failed me I learned welding aluminum and did it myself.

Two pairs of pedal threads have effective crank arm lengths of 150mm and 137mm respectively.





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Awesome! Now I need a video of you riding it :slight_smile:

Nice job on the UW. It is good that you have the spokes angles as a dragster wheel so you know what direction to ride it. Other wise you’d have to label or mark it in some way so the pedals would not be tuning backwards.

What kind of welder did you use?

Yes, we need photos/video of it in action.


I used a Lincoln Electric Square Wave TIG 200.

Who said anything about riding? :angry:

Just kidding.

Here is a video of me riding the 24" nimbus UW. Will shoot me riding the new UW later :stuck_out_tongue:

learn so you can make your own

Excellent ! In the late 90’s I learned on a Parker TIG so I could weld my own design frames, but your ultimate is an inspiration to me. Could be my next thing, it’s slow enough for me. Thanks for the video.
WOW 3d cutting laser great!

Thanks lobbybopser! Actually your suspension unicycles are a real inspiration to me (and thanks for answering my questions). I am planning on copycatting you suspension uni and are currently collecting parts :wink:

WRT the 3D laser cut parts, I initially tried to manually cut it myself but the lack of skill/tool made shoddy parts.

I would totally buy this if you made another. Name your price hahaha.

This is coincidental because I have a 36er rim I was just looking at that would be perfect for a plywood UW I want to make. I’m confident I could cut the plywood perfect but I have no clue how I’d get the pedals perfectly centered nor what would work for inserting the pedals into.

Nice job!
Here is mine:

I enjoy it tremendously, much more fun than the 24"


Thanks lobbybopser! Actually your suspension unicycles are a real inspiration to me (and thanks for answering my questions). I am planning on copycatting you suspension uni and are currently collecting parts :wink:

Use a GT LTS 2 frame of the earlier (90’s) design. There is a thread explaining its design under suspension unicycle.

Got it. Thanks.

UW parts for sale

I ordered enough parts for two UWs and now the leftovers are up for sale:

  1. 11 spokes (3D laser cut from 1"x2" 6061 aluminum tubing, 1/8" wall)
  2. 2 piece hub ( laser cut from 1/8" thick 6061 aluminum plate)

$330 OBO.

Additional parts needed to build a 36" UW:

  1. a 36" rim (the parts fit Coker aluminum rim perfectly)
  2. 1" OD aluminum tubing cut to ~1-1/4" long (need 4) to fit in the holes of the hub pieces for pedal thread

I’m going to caution you about a 36" plywood uni. It will be very heavy! You have to use material thick enough to support your pedals (you can use a Unicycle Factory Ultimate wheel insert kit (steel), but I think that’s intended for 3/4" plywood. I have a 24" Ultimate with 3/4" plywood and the Ultimate wheel insert. It’s fairly heavy, even with two Uni-Cyclone-shaped holes cut out of it.

A 36" built the same way will look cool, and keep on rolling after you fall off, but so heavy it may break pedals when it eventually does fall over. If you cut away a bunch of the plywood that should help, but it will still be fairly heavy.

If you hand-build, I recommend allowing for multiple “virtual” crank lengths. Don’t lock yourself into just one, it might not be what works best for riding.

I’m kind of curious… how does an UW compare to riding a unicycle while holding the seat out from in between your legs? I haven’t tried it many times, but when I try to remove the seat from the equation I always get a wheel to the leg the first time I pedal and promptly fall over.

Its harder then seat in front, but a little bit easier than dragseat

I found it to be much harder than riding seat in front. The entire challenge of UW is to keep the wheel from flopping from side to side, and jamming into your leg. Keeping the wheel vertical is trivial if you can use the seat, but with just your weight on the pedals it’s much much harder.

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The key is to practice seat in front with less and less holding the seat. In the end with the arm stretched and only holding with two fingers. If this gets easy, you are ready for the UW.


Other then the pedals being wider and you have cranks to bash your ankles on. How does a unicycle wheel without the frame compare to a UW?

Its much harder! The farther the pedals are from the senterline, the more of the force you put on the pedals will go into lilting the wheel instead of rolling forward. Minimizing Q-factor (by elimination hub and cranks) is essential to make it easier.

Thanks Eric, Makes perfect sense. I’m getting ahead of myself and thinking a freewheel UW might be fun :slight_smile: