Are you the person who made the CVT freewheel hubless 36”?
Sorry, it’s the first time I hear about that project. Except you mean the holy grail project- I am not that person. I have another holy grail solution in mind, but here I answer your question with an easy solution:
Here is a simple gearing idea I had in mind for some years, but in practice it is not as light weight and has more friction than i.e. a schlumpf:
Use a children’s bicycle inside a 36" wheel or larger and you have a geared unicycle. Fixed gear or freewheel or changeable gears or Nuvinci (the CVT 36" freewheel you asked for), like desired. Many people created a giant 36" sprocket for power transmission for low friction. In case you screw two 36" rims together, the children’s wheel can run in the gap between those two rims, like shown in the cross section of the rims. ‘Easy’ to build, but as with a twice, the friction will be high.
Ok I see your design and I love it, but I was referring to a dude on Facebook who did some wacky stuff with his, I’ll see if I can find it. And if you’re unable to test I have many 12” kids bikes and a 36” wheel, I can see if they will fit
Obviously this project is better in your hands. But as you show, it isn’t an easy fit. Also when the children’s bike is too long, it will certainly bend the 36" rim or require something more stable like 2 rims or a heavy steel tube ring (which I could bend fou you). But hey, it’s an idea we can actually dream about because it is possible to be built. At least it has the advantage to be a test machine for every standard hub on a unicycle, where the holy grail project had the same feature.
@Ulkicycling Any update on your nuvinci?
Hey @Nathan_Moore,
sorry, but I didn’t have time to go on with the project, as my wife just passed away.
It is not sure that this bidirectional Nuvinci idea really works. You are still busy searching for gearing ideas and have time for investigations?
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I’m sorry to hear about your wife. I’m still thinking on some ideas, the best one so far is replacing the thrust bearing with one piece
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Go-Go Gadget Wheel!
I don’t know if I’ve mentioned it yet but I’ve had an idea for a fixed gear CVT for a while and I just finished working out all the design kinks and started modeling it. I’ll update yall when it’s done. The final product will sadly have a maximum ratio of around 1/3 reduction (depends on how far I can push the design) and a minimum of 0:1, but with the use of an external jackshaft or possibly a two stage planetary set the range can be extended. Assuming I use my 9:1 jackshaft that gives a maximum ratio of 3:1 and minimum of 0:1, and I think that as a CVT a 3:1 may actually be rideable. It uses a modified “Swashplate CVT” mechanism explained here https://youtu.be/JngcaPHOIbA?si=jnq_sAL8WMSiWo9n and here https://youtu.be/0FwypgRLSZQ?si=0rtxmjVV6Re8tH_j
(Not me btw)