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With the UCI making the rules, that revised design would be on shaky ground, and the road would feel the same way in any sort of crosswind.
Both of these prototypes pre-date the Lugano charter, so UCI regulations were not a concern at the time. The crosswind issue though was a still a concern before 1996…well, at least it should have been.
I saw hubless concepts in the early 90′s and thought it would be ideal for placing the cranks on a recumbent. I wonder if the ‘concept’ would solve any problems today.
Hubless works only well with room temperature superconductor levitation, eh?
I love the look of hubless wheels, but have doubts about whether they’ll ever become close to practical. Some of the ideas floating around dream of magnets as bearings though. If magnets were used as bearings, I can imagine them being too weak for conventional hubs but strong enough on a setup like this…
Regardless of whether balls or magnets are used as bearings, there are two fundamental limitations. First is trying to match the tight tolerances of a hub bearing on a diameter that’s ten times bigger. The second is that on a conventional wheel, even a full disc, the rim undergoes a significant amount of deformation under impact load. So unless those magnets have a gap of several millimeters, they will be damaged on the first pot hole.
I actually used the Black Hole wheel in a graduate project that never went thru to final completion (hour record attempt…we lost funding). The wheel itself was actually pretty heavy, but once it got rolling it really, really was very fast. It was not ideal for the road. It was far better suited for the track. The biggest down fall with it was the fact that the bearings were not sealed very well. In fact if a little bit of road dirt got up into the race the wheel would tend to grind. I outfitted it onto my road bike and onto my track bike and rode it well. It was about 5 percent faster than a standard aero front wheel (yeah eliminating the spokes made that big of difference). Overall a very cool concept thta if they ever would have worked out the bugs with the bearing, would have been a game changer. The UCI ultimately did noot want to entertain the concept and banned wheels that mount as a single fork.
The photo of the Zipp bicycle with the Black Hole is my bike. I rode many of the early prototypes. The reason that the back of the “hole” was filled in was not for stiffness, it was for aero stability. Imagine a line, straight down from the bottom of the headset (not on the angle of the fork) and you’ll find that 2/3rds of the wheel is in front of this line. That effected crosswind handling. By filling in the back portion, it acted as a rudder and was actually very easy to ride in most wind conditions. The wheel did actually see a small production run.