Messing around with a Shimano Positron – Wandering and wondering
100 PRODUCTS HISTORY - POSITRON | SHIMANO
How To Set a Shimano Positron Rear Shifter - YouTube
Shimano-Road - In picture: Derailleur POSITRON ll. To develop safe, reliable and easy-to-operate shifting systems for any cyclist, Shimano announced POSITRON in 1974. This rear derailleur is equipped with an index system