Shimano’s Light Action design involved mounting the cable clamp bolt on a short lever that was independantly sprung, allowing some ‘give’ before the parallelogram was shifted. It was the direct descendant of the ‘cable saver’ on the Shimano Lark and Eagle designs.
I liked it a lot. Combined with well made, affordable, slant parallelogram derailleurs it gave a slick, fluid shift - tangibly nicer than SunTour’s comparably priced offerings of the time.
This example is a short cage version of the best of the Light Action range - with a satin finish aluminium outer parallelogram plate.
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