Help me understand what changed when SunTour's slant parallelogram patent expired...
I'm trying to understand how rear derailleur movement of the SunTour slant parallelogram works and was different than its contemporary competition, particular from Shimano. Consider these two Shimano 600EX versions:
Both seem to have the cage paralleolgram angled from "northwest" to "southeast", not unlike the SunTour Cyclone
, and unlike the Campy NR
(where the cage runs "north" to "south"). The Arabesque derailleur dates from well before the expiration of SunTour's patent. I think the later 600EX dates from after the expiration of that patent.
I'm clearly misunderstanding something about the way the cage moves between the earlier Arabesque and later 600EX derailleurs. Can someone explain this too me? Pointers to pictures or graphics demonstrating the slant parallelogram mechanism would be great. I found this YouTube video
, but the description implies that the Arabesque derailleur has a slant parallelogram design.