1930-ish - First gen Vittoria Margherita. Lever is for chain tension only. Push forward to loosen chain. While backpedaling, use hand/stick/foot to move chain side-to-side to change gears. Push lever forward to retention chain.
_MG_9137 by
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1935-ish - Second gen Vittoria Margherita. Lever is for chain tension only. Push forward to loosen chain. While backpedaling, twist triangle on top of the lever to move flappers to move chain side-to-side to change gears. Push lever forward to retention chain.
Frejus035 by
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1930-ish - Unknown brand, used by Learco Guerra. Use knob and lift up on seat tube to loosen chain tension by having hub assembly pivot down. While backpedaling, use hand/stick/foot to move chain side-to-side to change gears. Use knob and push down on seat tube to tighten chain tension by having hub assembly pivot up.
1934 - Campagnolo cambio corsa - Twist top lever to loosen quick release. While backpedaling, twist lower lever to move chain side-to-side to change gears. Twist top lever to tighten quick release.
Pecorari 042 by
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1947 - OMAC cambio sport - Jockey wheel is on a spring-loaded linear-moving rod to keep chain tension. While pedaling forward, twist lever to move chain side-to-side to change gears. After much effort. I never got it to shift gears without getting off the bike to move the chain manually.
Cambio Sport by
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1948 Frejus 146 by
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