FWiW there are internal gear cranksets too* , & LBS have converted Mountain bikes with mid drive motors
Hunters get to the top of the hill in the timber lands..

*Of note Efneo GTRO a 3 speed 28t + 2 Overdrives..

crank turns at a different rate than the chainring,,

A gear shift while stopped , I like that .. as a slow mover,,,





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