Shimano Ultegra Di2 breaks cover

Ultegra Di2 is numbered 6770 in Shimano-speak and is not compatible with existing Dura-Ace Di2.

Japanese component company Shimano today officially unveiled its electronic Di2 shifting system on the Ultegra road group, bringing easier, faster shifting to a much wider range of enthusiasts.

Designated 6770 in Shimano's number hierarchy, the announcement finally breaks the worst kept secret in cycling component history, being based on the principle of the successful Dura-Ace Di2 7970 electrically-actuated components but completely re-engineered for equal shift quality at a lower price.

There are still no final prices but Shimano's UK distributor Madison has confirmed that pricing should be roughly half that of flagship Dura-Ace Di2 components, less than mechanical Dura-Ace and not significantly more than the existing and continuing 6700 Ultegra mechanical groupset.

The colour will be the new glossy grey option recently announced for standard 6700, so that components unaffected by the electronic upgrade, such as brake calipers and cranksets, will be fully integrated from launch.

Shipments to shops, according to Shimano, will start in the Autumn although the best bet for securing an Ultegra Di2 group will be to buy it as part of a complete bicycle. 2012 bike ranges starting from late summer shipments will certainly include the new components.

So far, we have only seen and ridden pre-production prototypes but the initial impression apart from the new grey colour scheme is of peerless shifting and a considerably slimmed-down brake/shift lever compared to the mechanical lever. Indeed, it's very much like Dura-Ace but with an alloy blade instead of carbon. A pair of ST-6770s is due to weigh 313 grams as opposed to 445 grams for 6700 and 255 grams for Dura-Ace Di2.

The Di2 shifting will only be available for double cranksets, leaving triple users on manual and surely endorsing the general move towards wide-ratio cassettes on the rear - up to 28 teeth in the case of 6770 - for sportive and even light touring users. It also opens up the intriguing thought of how long it will be before we see an electronic mountain bike group now that the trend is moving towards 2 x 10 drivetrains.

According to Cycling Weekly's Stuart Bowers, Ultegra Di2 - which he's nicknaming 'Ui2' - will be "something we look back in years to come as underpinning a completely new direction for bicycle gear shifting." You can read his detailed report including reactions from bike manufacturers in this Thursday's Cycling Weekly magazine.

SM-BTR1 battery weighs 71 grams, charges in 90 minutes, last for months.




The front mech trims automatically as the chain moves up and down the cassette, meaning you'll never have chain rub again.


RD-6770 weighs 270 grams with a 11-28 capacity.

Shimano Ultegra Di2 website