Re: Dual-Chain drive train

On 12/27/2024 2:11 PM, AMuzi wrote:

On 12/27/2024 12:32 PM, Frank Krygowski wrote:

On 12/27/2024 10:35 AM, Zen Cycle wrote:

https://www.bikeradar.com/news/buffalo-utility-s2
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Made for developing countries to allow for easier transportation on cargo bikes, without the exposure and complexity of an external derailleur or hand-operated shifting (for an internally geared hub). It was developed and patented with the help of SRAM.
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It appears to engage one drive train or the other through a back- pedaling action, forcing the pawls in the freewheel to toggle from one side to the other.
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It's been tested for over two years in the field with great feedback (according to the article) and is now being marketed in 3rd world countries.
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The design won the Eurobike Gold award in 2024 for "excellence in design and innovation within the cycling industry"
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More information at https://worldbicyclerelief.org/s2/

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Thanks, that's more info than I was previously able to find.
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ISTR a 1960s hub gear with coaster brake that also shifted gears when backpedaled slightly. I never had a chance to ride one.
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 Many similar.  Cheap and effective, famously robust too. I made that comment the first time we discussed double ($$) drive chains on that vehicle.
 The original 1950s Bendix two speed had a cable to change gears. In 1960 it was replaced with the three 'automatic' versions whose mechanism is directly analogous to a Parker ball point in-out mechanism.
 https://www.youtube.com/watch?v=MhVw-MHGv4s
 [nice clear graphics]
 Fichtel & Sachs (later SRAM) made a very nice automatic unit as well and there are smaller volume eastern European variants too.
 Two of the Bendix 2-speed CB designs are currently produced under the Eagle [SOMA] brand.
 https://www.bicycleretailer.com/product-tech/2021/03/17/merry-sales- helps-bring-back-eagle-2-speed-coaster-brake-hub
 

Can you think of any reason why those versions haven't made their way into this application? Serious question....