[QUOTE=fietsbob;21546291]The Basics: little in the front Big in the back .. a 56 or 54 BCD Granny on a triple can have a 20t..
[Brompton 16" wheel 2 speed geared crank ,in low range, the pedals turn 2.5X faster than the chainring,
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I don't mean to contradict you, but my pedals turn at the same rotation as the chain ring, unless it's broken...
Edit: I did the research as instructed and learned about Schlump drives. They are amazing---and very expensive! Thank you,
Last edited by Bigbus; 06-22-20 at 10:09 AM.