Over the past four years professional riders have confidence in Shimano's Di2 electronic shifting technology, in all situations of riding. Now it is time to introduce this revolutionary technology into the Shimano Ultegra, making it available to a much wider group of road racers and enthusiasts. The advantages of Di2 (Digital Integrated Intelligence) are clear for everybody who has tested it: changing gears becomes easier, effortless and faster by simply touching the shift buttons. Control at the top of your fingers. Additional benefits include an automatic trimming front derailleur, unmatched precision plus super easy installation and adjustment. This allows automatic chain guide movement in response to the gear position of the rear derailleur. There is no more need for concentration on trimming when riding.
The SEIS (Shimano Electronic Intelligence System) is 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. The programmed motion allows quicker and smoother shifting with less danger of chain drop in all conditions and situations.
Braze-on socket. Clamp installation requires a separate adaptor.
