Electronic shifting filtered down to more affordable groupset
Shimano has launched a new electronic version of its second level Ultegra groupset. The Japanese components giant released the Di2 (Digital Integrated Intelligence) version of its flagship Dura Ace group at the end of 2008, and is now used by the majority of Shimano’s sponsored ProTeams, and has now rolled the technology down to its more affordable component line.
Like the comparable mechanical groupsets, Ultegra Di2 promises similar performance to Dura-Ace, but with slightly higher weight and less exotic materials. For example, the aluminium-bladed (carbon fibre for Dura-Ace) dual control shift/brake levers use the same SEIS (Shimano Electronic Intelligence System), and adjustable reach system, but weigh in at a claimed 313g for the Ultegra version, compared to 255g for Dura-Ace; similarly, the Ultegra rear derailleur weighs a claimed 270g, against the Dura-Ace’s 225g, and the Ultegra front derailleur weighs 162g, compared to 124g for Dura-Ace.
As well as the different materials and weights, the 10-speed Ultegra rear derailleur is able to handle an 11-28 cassette, while the maximum sprocket size for the Dura-Ace is 27 teeth. Like Dura-Ace Di2, the Ultegra groupset is completed with the same chainset, chain, cassette sprockets, and brake callipers as the mechanical groupset.
While the two electronic groupsets share the same rechargeable SM-BTR1 battery pack, which weighs a claimed 71g, the Ultegra group’s electronic cables have just two core wires, compared with four on Dura-Ace. The connectors are also smaller in diameter; 5.1mm, compared with 8.8mm, which means that the individual components of the two groupsets are not compatible with one another.
The cables will be available in different lengths to accommodate different frame sizes, and there will be PC connectivity for diagnosis and changing shifting order.
The parts, dubbed Ultegra 6770 (the mechanical parts are 6700), will be available in the new glossy grey colour.