Idle shaft for treadle-operated bicycle with left and right hand drive chains

摘要

The idle shaft (1) is mounted in a bearing housing (6) fixed to the bicycle frame (5). Pref. the shaft is driven on both left and right sides via chains (2,3) from the pedals. Pref. the freewheel mechanisms (7,8) in the bearing housing ensure the faster drive chain drives the idle shaft. Pref. a further chain (4) joins the idle shaft to the rear wheel hub.