1976: Shimano briefly made their own 10 pitch Dura-Ace track-specific system with 10 mm (approximately) pitch from about 1976 to 1980 May 6, 2013, progettopistavintage.blogspot.dk Quote: "... Somewhere in the 1970s, Shimano people got the great idea to reduce the chain pitch to 10 mm ... Somewhere in the 1980, the 10 mm pitch series were discontinued...." —called Shimano Dura-Ace 10 pitch.