Re: Only 14 gear ratios? Primitive!

On 12/4/2024 9:39 AM, Zen Cycle wrote:

On 12/4/2024 9:54 AM, AMuzi wrote:

On 12/3/2024 11:05 PM, Frank Krygowski wrote:

Bike transmissions: Derailleurs are easy to understand. Internal gear hubs are more complicated. (When I was teaching, I had our machinist do a cutaway of a Sturmey- Archer AW hub and mount it on a display stand near an explanatory poster, so interested students could see what made it work.)
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Rohloff 14 speed gear hubs are an order of magnitude more complicated than AWs. But this new gizmo makes a Rohloff look like child's play. It's a true continuously variable transmission, with an infinite number of gear ratios, that is completely gear-based. No slipping surfaces, and supposedly minimal friction losses.
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Here's the link to the half hour explanation video:
https://www.youtube.com/watch?v=mWJHI7UHuys
You may want to start at about 14:30 before returning to the beginning to digest the super-complicated explanation of it's operation.
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No info in the video about prototype weight, efficiency, etc.
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Brilliant and clever! Thank you.
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I can only see complexity, cost to fabricate and weight as downsides, none of which would be deal breakers for some applications. Motor power for example.

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It actually seems to me to be significantly less complicated than a standard automatic transmission
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Sort of the inverse of fixed, which are dirt cheap, light and reliable at the cost of zero gear variance.
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Nothing a good pair of legs can't handle :)
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 I have to admit I don't know much about modern electronic control slushboxes (except to avoid them) but the geared CVT is much more complex than what I drive* and infinitely more complex than what I most often ride (fixed)
  * https://corvair.com/user-cgi/catalog.cgi?show_page=130