***** 1. You do realize that on this bike and on most bikes the weight of the whole bike and the rider are "unspung?" It is not a "problem." 2. Why would there be "friction slippage?" - You do realize that when you ride your bike the way that your tires makes contact with the ground is "friction?" If this was a real "problem" bikes, cars, and pretty much all other vehicles would not exit. 3. Why would the rim deform? 4. "sudden breaking stress" I am not sure what this means.... can you clarify? I think that you are trying to invalidate a new technology without a basic understanding of how it works. I do not think that any of the things you list are actual "problems." Being an engineer, I think this is a really clever idea! I'm sure that there are problems in the design, but I am also sure that there are problems with any new and innovative technology.

Audrey Jackson 1. For bikes that don't have suspension at all, you're right the whole structure is unsprung so it would not make sense for me to have been talking about frames like that. For bikes with suspension this design places a lot of weight below it which defeats the purpose of the suspension. At low speed it's not a problem, at high speed it will give a horrible ride and cause a lot of wear and tear on the components. 2. I'm talking about the friction needed between the drive wheel and the inside of the rim. Naturally, we already rely on friction between the tire and the road but we really have no choice about that. What this design introduces is even more dependence on surface friction, when there are plenty of alternatives that do a much more reliable job, eg. chain, belt, gear, hub motor. 3. Because there are no spokes to give it strength! 4. When the brake grips the rim the inertia of the bike still pushes the mass forwards, and the primary point it acts on is the center of the wheel. In a normal wheel this point is also connected to the entire rim by spokes forming a single rigid body, so the rim is unable to move relative to the hub and the overall effect is to stop the wheel turning by having fixed it at two points. Any sudden braking that overwhelms this arrangement will result in slipping either between the brake caliper and the rim, or between the tire and the road. With the design in this video though, there are five separate rigid bodies (as opposed to two in a regular bike), one of which (the rim) is not even really a rigid body since it's so precariously thin, able to move relative to each other via a large number of complex failure points. Fixing one point on the rim does not directly result in preventing the wheel from rotating, it just means that the wheel will tend to rotate around the point that was fixed. True, the other components that make up the wheel will not let the rim simply rotate around the caliper point, but the stress of sudden braking has to make its way through a needlessly complicated structure of multiple rigid bodies and bearings. I'm not trying to invalidate this just for the sake of ragging on 'new' technology. 'New' is in quotes there to follow your description, because the means to do this has been around for a couple of decades at least. The fact that this design is not all over the place by now speaks for itself. I like the novelty factor, but I'm a hardcore 'function over form' guy and I don't see what this design offers that a more orthodox (and yes, boring!) design could not accomplish (hmm... more torque perhaps?). I think it would do just fine at low speed on smooth clean surfaces, but there are plenty of smarter and simpler designs which can do the job with much less fuss, and you can retro-fit them to an existing bike with a reasonably priced DIY kit and have none of the issues I mentioned.

***** 1. I would add that it is not a "speed" issue. Unsprung weight changes suspension dynamics when speed is combined with rough terrain. It would mostly be applicable to hi-speed mountain biking where a large unsprung weight will effect how the suspension adjusts to the terrain at hi-speeds, but I still don't see a reason to think that it will give "a horrible ride" or "cause wear and tear on the components" even in a hi-speed off-road environment. I am sure that in this specific case the riding dynamics will be different, but I would have to feel it to see if it makes the ride "worse." Why do you think that would it "wear out suspension components" - these components are designed to be able to support a lot of weight and all sorts of impacts. 2. I understand the friction that you are referring to, but still this is the same mechanism that transfers energy from the tire to the road. I'm not even sure that the drive wheel is just frictionally coupled, there might be something else to it that we can not see in the video. But even if it is just friction, that would couple the drive wheel with the the bike rim with the same efficiency that the tire couples with the road. I actually think that this is a really efficient system and I don't see any reason to think that this would slip any more then the tire would slip on the road - in fact I think it would slip a lot less, because of the profile of the rubber and the greater amount of surface area that makes contact with the rim. 3. Yes, but bike rims don't just "deform" on their own. What would make it deform - are you referring to an impact deforming the rim? If you're referring to an impact - you have a good point - I could definitely see a scenario that would deform this rim more than it would deform a rim on a normal (spoked) wheel. I don't know if they have a fix for this, but I could see this being a problem. 4. I still do not understand this one. Break pads grip the sides of the rim - as they are designed to do. The rim stops spinning and the bike breaks. Where are all these "failure points" that you are referring to? I am also very skeptical when it comes to new things and I agree that the fact that this hasn't been around until now very odd, because this seems so obvious to me now that I see it! I spent a while thinking about why this theoretically wouldn't work and I have some good ideas - but the bottom line is that it does. I have not ridden one (I assume that you have not either), so I am left guessing about how it handles, but this is something that requires a hands-on review!

+Audrey Jackson 3. Hit a curb at a medium speed. A normal spoked wheel would be fine, this wheel would deform. Look at the very end of the video and you will see the wheel spinning 'un-true'. I hope they figure it out, this is awesome!

+Darren Clark thats a good point i didnt think about that. im hopping curbs all the time

+Dimitri Boyarski yeah the market is kind of flooded but this thing looks pretty impressive.

agreed

+American Writer all weight is removed from the frame for 1.

+tin fingers so now you have the weight in the frontwheel, which mackes steering harder.

theonlySTABEL motorcycles can have 25 x or more weight on the front wheel then a bicycle fitted with this wheel. do motorcycles require significantly more force to steer the bicycles when moving? both can be controlled with no hands by simply adjusting the weight to one side of the other.

they did ride through water and snow in the video, also notice they were riding in an urban environment, not on trails or mountains, I don't think they designed it for hard offroad use.

How is it i just hear about this, and jerry's here.......hahahahahaa

+Noneof Urbusiness You're right. Just look at the rim wobbling at the end of the video. There's no way to true the rim.

+Noneof Urbusiness This is definitely a problem but after looking at the wheel a couple of times, it seems possible to overcome by playing with the support rollers and their angular position and maybe adding one more to minimize the un-supported areas therefore giving the rim some support. They can also play with the structure and material of the rim. Here they seem to be using a normal rim without spokes, bad idea :-) My second highest concern is the weight. It seems that this device's weight is high. Turning at speed as well as other maneuvers maybe affected. In the end, it is not cycling anymore if you dont have to pedal LOL

+Rich Rivet day xxv vsvfxcx

not to mention that I suspect that since the rim is capture at the point of pressure and not at the center via spokes, any deformity is rectified at that point and not noticeable at all.

+Noneof Urbusiness yes and if the rim gets damaged or and if anything gets inside the wheel, there is a lot of opportunity for that, it could easily jam or derail the rim.

+videobuoy look at the history of the bike wheel and you will understand... it just became standard and at the time iti was invented it was the only way to implement the technology it was derived from the horse carriage wheel... it was not a breakthrough it was just copying a technology that was PREVIOUSLY implemented... The spokes in your wheel became a standard in manufacturing because of the ease of production not because of the efficiency of the tech. spoke wheels have the same as the QWERTY Keyboard and the DOVRAK Keyboard layout... it was a fluke of the industry.

***** I ride bikes and have done for many years and am familiar with 3 spoked wheels. (aren't they nearly always made of carbon fibre?) I would suggest that there is a huge difference between this monstrosity and a carbon spoke - Trust me this thing is not going to set the world alight in fact with all that weight in the front wheel I'd suggest the handling would be bordering dangerous.

Frank Nazario so Frank perhaps you can tell me why Olympic road bikes and Tour de France bikes still use SPOKES?

videobuoy buoy sure ... the answer is very simple... spokes are light ... actually very light solution for that specific task... but and here we go again... hit that wheel laterally and its gone also... do you know how many hours a tech spends tensioning and alingning the wheel and spoke so they are perfectly vertical and straight????

Truing a wheel doesn't take that long if you have the right tools and you know what you're doing.... it's still the best solution out there - if it wasn't then they wouldn't use them in the Olympics or the Tour de France - I have to say I have no idea what your point is.

+John H Baumgaertner Same reason, I like the car alternator on top of the engine and not way down at the bottom. It can mean life or death some times! I had a car stall out, when after a big rain drove through a large water puddle on the road and flooded the alternator, which was located at the bottom of the engine.Lucky me, I got through some how, but many cars didn't.

+Derek Kerton Also, the ring of the wheel is weaker because of the lack of spokes holding it round. Also, bumps will put difficult forces on the three mounting points. Also, braking forces will put complicated torques on the wheel, and we know spokes can handle those forces, but we'd need to see how well this design handles strong braking. Also, there are three points of friction in this wheel, compared to just one with a hub and spoke wheel.

+Ted Berner Oh and I read about bent rims, yada yada. Add an inner drive ring with multiple connection points to the tire rim. The drive ring would add a lot of strength and in the event the rim does take a hit, it's much less likely the drive ring would go out of round. Naysayers just lack vision.

+Cristi Neagu What if i told you that it still works like a wheel and it's still a wheel?