Fascinating idea but not sure how you get the wheels strong enough without the tension of spokes? Potentially a far stronger carbon rim, that is around the thickness of a mountain bike wheel with an inner semi-hollow hexagonal matrix (like a honeycombe) might work?!? I suspect it would still flex a great deal more than a current wheel, but fine for cycling around town
It's an interesting design study... As for the wheels --- a composite rim would be strong enough - however the rolling surface is a challenge - it would need to be a rail with 'bogeys' that keep the wheel aligned and firmly attached to the frame. On the crank mech - something more than the ratio shown would be nice --- assuming one tooth/in would give roughly a 50x88 ?? Aerodynamics would not be much a concern on a bike that would barely reach 5-10kph at 150 cadence
I thought the same about how the wheel would be held in place - it would have to be be constructed like ball bearings with a rotating rim with tyre on the outside and an inner rim firmly linked to the frame on the inside. That's not going to be any lighter than a hub and spokes. And how would you lubricate it and keep dirt out? How would you fix a puncture?
The transmission ratio is not the only problem about the direct drive - most people would also want variable gear ratios and a freewheel. There would have to be something like an IGH in the center of the crank.
His invention is a bicycle that has no spokes, folds to a fraction of its full size, and is a speed demon. The glistening green colors makes the bike look like a perfect addition for the Green Lantern’s superhero gear.
I really had to force myself to keep reading after that.
Basically it's a concept that has been doing the rounds from various designers for some time now and basically it will never take off. Frame flex is going to be a huge issue here especially where the front wheel joins the frame.
Frame geometry is all over the place and the wheel base is seriously risky.
There is a reason why the bicycle has changed very little in the past 100 years.
Well an unobtanium, frictionless slide rail at the front ... and similarly at the rear with a zero-loss planetary gear xmission and you'd be getting closer. There is a pretty good introduction to hubless wheels on the Osmos site .. http://www.osmoswheel.com/pages/concept.asp One of the best examples of an actual working hubless wheel is right in our backyard at the Tokyo Dome Ferris Wheel!
Somewhat tangentially-related, but this reminds me of a conversation with a guy in Tokyo who was convinced his friends at some fancy tech university in the US had developed a perpetuum-mobile device. My bullshit alarm went off only marginally harder at that time than when I read through the article in the original post.
Those rims just need some Bose-Einstein condensate superfluidity going on and you'll be in business.