In 2003, four years after EGS went bankrupt, Franck Savard was still dreaming. This time of developing the design of the EGS Up Cage to incorporate a sophisticated spiral grooved drive that would shift the rear derailleur in a complex pattern - all by operating a reasonably simple twist grip. You can only gasp with admiration - I do hope that there is a beautifully machined prototype sitting in a workshop drawer somewhere.
Franck was considering this technology in one variant, with a single cable per derailleur and a sprung spiral, and also in a second variant, with two cables per derailleur and no spring. 'One cable and spring' or 'two cables and no spring' - its a dilemna almost as old as the derailleur itself.
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EGS Up Cage 1998?