On Thu, 18 May 2017 13:10:48 -0500
Tim Wescott wrote:

snip
So -- any thoughts on an easy way to gear the thing down? I just
recommended to the customer that they put two chain rings on the crank,
so that they can drive the pedals at one speed and the bike at another.

Not cheap, but have you seen the NuVinci hub:

https://en.wikipedia.org/wiki/NuVinci

https://www.amazon.com/s/ie=UTF8&ind...=NuVinci%20hub

--
Leon Fisk
Grand Rapids MI/Zone 5b
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