As an addition to the mechanical Dura-Ace 7900 series, the electronic Dura-Ace 7970 will deliver state-of-the-art technology that will give its users a revolutionary road riding experience. Di2 stands for 'Digital Integrated Intelligence'. This innovative shift technology is still based on the Shimano Index System (SIS) that has proved its superior gear changing characteristics over the years. The big difference is that in this case , the shifting action is provided for by electronics instead of mechanics. This electronic shifting system was tested extensively over the past two years by several professional riders in all conditions possible, such as rain, mud, low temperatures, cobble stone roads and combinations of all of these at the same time. Dura-Ace 7970 series consists of Dual Control Levers, front and rear derailleur's and a battery kit combined with remaining 7900 mechanical components. The Shimano 7970 Dura-Ace Di2 Front Derailleur is part of the new 7970 series.
The difference in the effort and time taken for front shifts between Dura-Ace mechanical and Di2 is truly staggering: with programmed automatic motion at the touch of a switch the Dura-Ace Di2 front derailleur is quick, smooth and effortless, making for unmatched drivetrain efficiency. The biggest difference you will notice is just how much quicker and effortlessly smoother shifting on the front chainrings is, even under load. The difference in the effort and time to actuate the shift between mechanical and Di2 is truly staggering. The removal of traditional mechanical cables in favour of electrical wires not only eliminates poor shifting caused by contaminates, corrosion and stretching, but provides effortless gear shifts. The front derailleur also trims automatically; the cage moves in response to the position of the rear derailleur on the cassette to ensure no chain rub and a quiet unobtrusive ride, enabling you to concentrate on the road ahead. Braze-on fit as standard; if your bike does not have a braze-on mount seat tube adapters are available.