spokeless bicycle

That looks like it weighs 500 pounds! I wonder if these engineers also ride bikes?

singlespeed29er   02.17.10

As interesting as this is (and it does look cool) it is inherently inferior to a traditional spoke-hub wheel for two major reasons.

Both are based on the physics of spinning dynamics (which I would think that a student would research even a little if they were going to make a new type of wheel).

First is the problem with inertia. For any spinning object, mass at the outer edge has exponentially more inertia than the same amount of mass closer to the center. This is why traditional wheels reduce the rim to the bare essentials, while placing their load bearing elements at the center. This wheel does the exact opposite. The entire structure of the wheel is exactly where you don't want it, at the outer edge. This would be particularly evident on any steep hill climb where a cyclist is required to basically break the wheels static moment with ever pedal stroke. The only real upside is that once you got this wheel rolling (going down hill or on a long flat), it'd be a lot easier to keep rolling than a traditional wheel.

Secondly, this wheel can never be as light as a spoke-hub wheel made of the same materials. A spoke is a tension member which "hangs" the hub. Steel, aluminum, and carbon fiber all work far more efficiently in tension than in compression. However, with this wheel the hoop must resist it's own deformation. And to do this is must act in both tension and compression. It will ALWAYS require more material than a spoke-hub wheel, and thus ALWAYS weigh more.

It looks cool, and is a quirky mechanical challenge, but is ultimately a flawed design.

hairpiece   02.17.10

Good project which could be just awesome if a designer work on it !

stasiak   02.17.10

front wheel has spokes, fail.

mttttttt   02.17.10

gyro balanced storage basket? nahh.

prokes   02.17.10

I'm definately glad I didn't go to Yale for my Engineering degree!

bdf   02.17.10

I didnt realise spokes were a problem on bikes...

design1000   02.17.10

That's pretty sweet.
a nice one-off design, definitely not replacing any traditional wheels,
but cool nontheless.

eirosnevermore   02.17.10

....what's the point of the design??? symplicity?, functionality?, cheaper to manufacture??

llhote   02.18.10

Instead of designing an improvement on the classic spoked wheel bicycle design, these students have wasted their time making the design less functional and heavier. Just because something can be made, doesn't mean that it needs to be.

I want INNOVATION with PURPOSE!

Wowe   02.18.10

It's great to make mistakes and learn from them, I'm sure these guys have learned a lot. Must have been fun. As 'hairpiece' points out in comment #1, this will never work. By the way, there are a few hub-less motorcycles made, i don't see the big news.

felix   02.18.10

For far more interesting cycling literature check out this site: [url://www.2010cssc.com]2010cssc[url]

eric   02.18.10

spokeless wheels, wheather in motorcycle or in bike design are stupid ghosts which obviousely are hard to kill.
Thing is, it is possible to do it but it is stupid at the same time and designers, and as we could see also engineers, fall for this idea for centuries.
Why? Because it looks different and new and because nobody builds it in a real and successfull serial product, it always will.
The efficiancy of this one compared to a vehicle with a hub is dramaticly uneffective. This means you need a lot more power to move it. Because of the guidance which is needed for this wheels you have a lot more friction. It is a lot heavier and because of more tolerances in the guidance it will feel strange driving it.
All in all, one can say, it doesn't work - compared to other concepts its way behind. Since centuries, I think at least since the 60s this hubless concepts are sold to us as the future, but it is only the future of the past.
As long as designers get prices for such kind of bullshit the hubless wheels will be our future in the future, too. A viciouse circle.

Maximilian Näther
www.zoom-designagency.com

ZOOM designagency   02.18.10

How is this progress?? Its an industrial designers fantasy born from science fiction visions. Edge driven saw blades make since for getting a greater cut depth. For a bicycle its senseless. Electric assist hubs with spokes exist, on top of that.

If nothing else... the driving mechanism and support should be as close to the ground contact patch as possible to reduce lateral flex and reduce all the beefy structure. But still misguided.

If they had applied rigorous thought and existing bicycle design theory, they would not have anything remotely like this. How about making a more aerodynamic yet utilitarian human powered transportation? Light weight, cargo recumbents?

How can Yale encourage this crap?

not impressed   02.18.10

Well I don't like it one bit, but what else do students have to design now that we have all of these great products from Apple? Hey how about reinventing the wheel! But only the back, because the front is too difficult.
Sorry, I couldn't help myself.

Salvador Dalli   02.18.10

I like it. Font get discouraged, a clever is not always obvious to ordinary people. Two hundred years, a bike looks rear by today;s standard.

You can improve on this with spokeless front wheel also, then it is even better. For the rear wheel, you can make it slimmer by using a fixed rim like the inner ring of a ball bearing with a hole in the middle. You can attach the bicycle frame to the inner rim. Use rollers between the rim and the tire rim. Then it is exactly a roller bearing design, The teeth is on the side of the tire rim. Use shaft drive to run on the side teeth of the tire-rim. The peddle would turn the shaft rather than by chain. Then it would be much cleaner and elegant.

I am visiting relatives in China, once I return to Hong Kong by March 5, I can put that on a drawing for you. My mobile number in Hong Kong is (852) 9870 9542. Victor Lai

Victor Lai, (852) 9870 9542   02.18.10

ugly and useless...

waldo   02.18.10

Victor, go for it. You're right, it's a roller bearing! Tho hairpiece is right about tension-compression of metal and carbon. Would ceramic work better?

Forget about looks for now . . .

Tom P   02.18.10

What's the benefit??? Why try people to give bikes and cars a futuristic futuristic look by making them spokeless (ass it was invented in the 80's er 70's)? I cant take it serious!

Spokeless - useless

pip   02.18.10

Not a single person noted that this is a complete ripoff of a 30 year old design by Franco Sbarro...............and poorly executed one as well. "Hey youngins', pick up a history book once in a while"

Next year geodesic domes/homes.......I'm sure you've never read about Buckminster Fuller.

Old Enough to Know Better   02.18.10

Interesting concept. As someone from a furniture design and manufacture background, it's not exactly my area of expertise, but as someone who like to ride a bike, I'd love to take it out for a spin. All the issues raised about it being a pointless and unnecesary design are true, but this thing reminds of the retro styled beach cruisers that came back into vogue a few years back. They were a step backwards in bike engineering, ie. heavy, but geez they were popular.
I could see bike nerds all around the world wanting this.

D Hipwell   02.18.10

stupid! Just try to jump ... with that thing...

cizu   02.19.10

As a mechanical designer I appreciate the construction of the large "gear" from a regular piece of timing belt rather than an expensive machining process to create a all steel/aluminum one. That alone is reason enough to celebrate their creation. If you don't like the design, you don't have to dump on it. Like the saying goes, "If you can't say something good, don't say anything at all."

Harvey Millstone   02.20.10

Boring inputs, all of them! Is everybody only handy with criticism or does anybody have something to show... And put in this "arena".

Laughed a lot though......

What do you have to show?   02.20.10

A few things that people didn't mention:

1) Spokes break
2) Over time as additional sprockets have been added across the back, the frame dimension at the axle has had to be increased
3) It is tricky to get balanced tension to that the wheel is equally strong from the left and from the right
4) Sbarro's design was more for motorcycles and featured an external chain, rather than an internal belt.

Don Hopings   02.20.10

That's at least a true hubless wheel!! All Sbarro did was use a hub that's as big as the tire, and then pierce that hub. It looks great, but there is nothing revolutionary in the technique, and oh, guess what, no one ever used again either in production.
I'm impressed by what these guys did. They made a number of mistakes, but in 6 months in engineering school, it's an feat to reach this level already.

Tomm   02.20.10