“When you sit down to reinvent the wheel, people think you are crazy. When you succeed you get something that is visually stunning as well as technically advantageous.”
So I followed the link and browsed the site for a few minutes.
A French guy has been working on this wheel design for years. Basically, it’s a wheel with no insides… just the rim and tire. It’s wierd to explain, so let me just give you the links.
That is probably the coolest page I found. It shows why this wheel works better than tradional ones. And most importantly, it has cool photos showing the wheel on different vehicles. Check out the bicycle at the end!
There is a picture somewhere (perhaps on teh cool unicycles page of unicycle.org?) a picture of a ‘hoop giraffe’, which is a really snazzy looking uni with a ring attached as the wheel. It is perhaps one of the most amazing unis I’ve ever seen, and I want one.
There is a picture of the hoop wheel giraffe in this thread. The photo is by Lars Lottrop. The rider is in a Chinese acrobatic troupe. Lars did have that photo on his web site in a gallery but I can no longer find that particular gallery.
I can see the hubless wheel being used for a geared unicycle similar to the Purple Phaze or the Outta Phaze. It would still be possible to suspend the pedals in the center of the wheel so it would be like a standard unicycle. There would be some sort of drive mechanism (probably a chain) going up to the rim where it would drive the wheel. There are gearing possibilities there. It would make for an interesting uni.
One problem with those wheels for a unicycle or bike is how do you keep the wheel from flexing. There are no spokes to add strength and structure to the wheel. The wheel would taco easily. The rim would have to be so overbuilt to add strength that you’d end up with a heavy wheel.
Similar hubless wheels have been used on custom motorcycles. They actually work in the real world. Anyone with the money could buy a custom motorcycle with that type of wheel.
How about having the drive system at the bottom self contained with the cranks? so the cranks are only just inside the rim, something like this. It’ll only work if the wheel is large and the cranks are short enough not to hit the floor, but it would make for a more compact 36"+ uni. And it can include gears or brakes in the lower ‘pod’.
actually I have been toying wih such an idea since last year. My real problem was that, not being a mechanics ,I do not know how to build a big ring around which the wheel turns.
basically my idea is an hybrid between a classic wheel and such a hollow wheel . the hollow part being around 35cm in diameter and the rest being a “normal” wheel with spokes. so it’s just as if you had a big hollow hub.
why this? because then you can built your gearing mechanism “inside” that big hollow place (for instance something build using chains)
another point I was considering (but not sure) is that the axle of pedals might not be exactly at the axle of the wheel…
Not a bad idea LooseMoose, but tight turn would almost be out of the question. One of the bicycles on that site had the front wheel attached at the bottom, which doesn’t seem to give it much clearance. Those designs look cool just for cool factor, but seems like they sacrifice too much strength and practicality. When you’re attached to the rim at the bottom, all you have for clearance is the thickness of the tire. I have enough trouble hitting my pedals on the ground with my trials uni. Your design looks cool, and would be good for parades or something, but those turns could be tricky.