RD-6770 Rear Derailleur (10-speed)
Fast, precise and smooth electronic shifting – even under load
Easy electronic adjustment system
Crash saver function
Wide gear ratio – Compatible with 11-28T cassette sprockets
High performance lithium ion battery (7.4V)
Easy to assemble/remove for charging
Charging time: maximum 90 minutes
The Ultegra Di2 components and all the other electronic necessities total $1,595, or $2283 for a complete Ultegra Di2 build. The mechanical Ultegra 6700 group retails for $1,500.
For comparison, Dura Ace Di2 costs $2749 for the electronic necessities and $3927 for a complete build. A complete mechanical Dura-Ace 7900 group costs $2690.
Reports from users is that Dura Ace Di2 certainly works. It is an engineering marvel and just a joy to use. The automatic trim of the front derailleur is certainly a nice advantage. But the real roadblock is the price of $3927. So Ultegra Di2 at $2283 can really get this cool stuff in the hands of consumers. Instead of going mechanical Dura Ace, the consumer now has a choice of going with Ultegra Di2.
Riders will have to pay a weight penalty, as the new group tips the balance, according to Shimano’s claimed weights, at 2,458 grams. Dura Ace Di2, by comparison, weighs in at 2,108 grams.
Some individual pricing of Ultegra Di2:
Shifters: ST-6770 Dual Control Levers -$444.99
Rear Derailleur: RD-6770 – $339.99
Electric Cable Junction: SM-EW67-A-E – $404.93