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 ST-7971 Dura-Ace Di2 10 Speed TT and Triathlon STI Levers are part of the 7970 range.
The most advanced level of shifting technology: at the touch of a switch Dura-Ace Di2 is quick shifting, smooth, and effortless. The removal of traditional mechanical cables in favour of electrical wires eliminates poor shifting caused by contaminates, corrosion and stretching, and also provides effortless gear shifts. Simply pressing tactile buttons allows effortless and comfortable shifting even when your hands are cold. Shift switches are located in an ergonomic easy to reach position on the side of the aero brake lever. This switch positioning now gives the added advantage of being able to quickly shift while braking into corners and accelerating out previously not possible on a TT set up. Brake levers are lightweight thanks to aero carbon fibre lever blades, carbon composite bracket body, and alloy fixings. Brake lever pivot is positioned to increase power in combination with BR-7900 brake callipers. The Di2 STIs are also compatible with the FlightDeck computer (SC-7900), measuring important data such as heart rate, altitude, cadence, gear position, battery indicator, and more. Levers are supplied without electrical cables, as these need to be ordered separately to suit.