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Someone coming up with the idea to re-invent the wheel ! :eek:


Definitely unusual and it works !


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Ride on ! :)
 

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Guess it opens up some possibilities when it comes to steering geometry. But it must surely move weight from the hub and outwards, thus increasing rotating mass.
 

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I would think it reduces rotating mass, which would reduce the gyroscopic effect that stabilizes all two-wheeled vehicles. Although I'm sure there's enough mass in that rear tire to stabilize Britney Spears.

I wonder if it increases unsprung weight, though. That's not going to do the handling any favors, if so.

This isn't the first hubless wheeled motorcycle I've seen. Cycle World did an article about one several years ago.
 

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I would think it reduces rotating mass, which would reduce the gyroscopic effect that stabilizes all two-wheeled vehicles.
How do you recon it does that? If they take out the hub, won't they have to increase the rim-weight to add the stiffness lost? Also don't they have to have some sort of "double-rim" or something out there, increasing weight even more?
 

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It's an interesting concept; but IMO the bike itself is just another high priced Parade Float! Without a rear fender, what happens if your butt comes into contact with that big rear tire?:eek::D---James.
 

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How do you recon it does that? If they take out the hub, won't they have to increase the rim-weight to add the stiffness lost? Also don't they have to have some sort of "double-rim" or something out there, increasing weight even more?
These are all assumptions, but that doesn't mean I can't argue about them until the choppers come home! :D

I picture the actual, rotating wheel for this to be roughly what you'd get if you cut the spokes off of a regular wheel, and machined a (cross sectionally) flat surface onto the inner face. Now take a hollow axle, and put it on your axle stretching machine, and crank it up so the outer face of the axle is big enough to come within a few mm of the inner diameter of the wheel's inner face. Leave enough room for a bearing, put the bearing between the 'axle' and the wheel, and then put it all together.

Unless I'm hugely mistaken about how these wheels are built (a distinct possibility, I'll be the first to admit), the result will be a large, non-rotating 'axle', and a wheel/tire assembly with much less mass than a conventional setup. Maybe the "double-rim" you refer to is what I'm calling the 'axle' and wheel. If so, I'd still think only one of the two pieces that make up the double rim would rotate.

As for stiffness, I think a wheel gets a lot more of it's stiffness from the lip against which the tire bead seals than from anything else. And the wheel is in contact with this big, strong 'axle'/double-rim, and that will also add stiffness.

Any Mechanical Engineers out there care to chime in? This is just a phyzzicist makin' it up as he goes along here... ;)


I sure hope this thing handles better than a wet cucumber approaching an icy bridge!
 

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Er.....what he said!:D What kind of load and gyroscopic force change would occur with the forks in this position I wonder?:confused: The bearing surface on each wheel must be massive. I would imagine it would be stable but hard to lean over or turn.

Cheers
Jeff:motorbike2:
 

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These are all assumptions, but that doesn't mean I can't argue about them until the choppers come home! :D

I picture the actual, rotating wheel for this to be roughly what you'd get if you cut the spokes off of a regular wheel, and machined a (cross sectionally) flat surface onto the inner face. Now take a hollow axle, and put it on your axle stretching machine, and crank it up so the outer face of the axle is big enough to come within a few mm of the inner diameter of the wheel's inner face. Leave enough room for a bearing, put the bearing between the 'axle' and the wheel, and then put it all together.

Unless I'm hugely mistaken about how these wheels are built (a distinct possibility, I'll be the first to admit), the result will be a large, non-rotating 'axle', and a wheel/tire assembly with much less mass than a conventional setup. Maybe the "double-rim" you refer to is what I'm calling the 'axle' and wheel. If so, I'd still think only one of the two pieces that make up the double rim would rotate.

As for stiffness, I think a wheel gets a lot more of it's stiffness from the lip against which the tire bead seals than from anything else. And the wheel is in contact with this big, strong 'axle'/double-rim, and that will also add stiffness.

Any Mechanical Engineers out there care to chime in? This is just a phyzzicist makin' it up as he goes along here... ;)


I sure hope this thing handles better than a wet cucumber approaching an icy bridge!
Hey, this is a fun discussion. I don't really know jack-s about such things, but it sure is fun speculating. That is probably the only good thing to come out of that fugly bike ;D

Anyway, I'm with you on how the thing might be constructed (double-rim / circular-axel&wheel). And you might be right about that most of the stiffness that keeps the wheel wheel-shaped is out there. But even if only a little bit of the stiffness is provided by the spokes and hub, then that stiffness lost (when designing hub-less) must be compensated for by added stiffness in the circular-axel&wheel. Right? And that weight is by definition further away from the center. Thus leveraging rotating mass further out and thus being more significant.

Besides, the circular-axel would have to be of less mass than the hub and spokes.

Anybody else care to speculate??
 
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