Shimano Ultegra Di2 RD-6870 Rear Derailleur 2x11

In 2008 SHIMANO first introduced electronic shifting to road cycling in its Dura-Ace 7970 groupset. In 2011 it became available for Ultegra. Now it's also available in Ultegra 6800. Ultegra takes pro-tested technologies to a wider audience. Whether it is a mechanical or electronic shifting interface, Ultegra provides the highest quality outside professional racing.

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.

Features of Shimano Ultegra 6870 group:
The derailleurs are more compact and lighter than their predecessors. The rear derailleur is updated with an automatic protection system that moves the cage out of harm’s way in case of a crash. There are two versions of the rear derailleur. A SS for cassettes up to 28T and a GS for cassettes up to 32T. The 32T GS rear derailleur in combination with a compact front crank setup offer a full wide gearing setup. Both rear derailleurs are featured with multi shifting. With a single press and hold of the shift button the rear derailleur goes all the way up or down the cassette. Or, when programmed at the E-tube platform, two or three gear shifts. Also the speed of gear shifts can be adjusted. In five steps, from very slow to very fast.

Shimano RD-6870-SS

• Precise, lightning-fast-shifts accross an 11-speed cassette, whatever the conditions, with just a button click
• More compact and lighter, with E-tube connections to simplify installation
• Automatic crash protection moves the cage out of harm's way
• Wide link design to reduce shifting deflection
• Low sprocket 23-28 teeth

Shimano Ultegra RD-6870-GS

• Precise, lightning-fast-shifts accross an 11-speed cassette, whatever the conditions, with just a button click
• More compact and lighter, with E-tube connections to simplify installation
• Automatic crash protection moves the cage out of harm's way
• Wide link design to reduce shifting deflection
• Low sprocket 28-32 teeth

Note: In order to ensure proper functioning of the electronic Di2 drive system, all components require the same firmware version. The optional diagnostic device allows for reading out or updating the firmware version. An operation of components with different firmware versions may cause a malfunction or loss of function.

E-Tube

The Ultegra 6870 products are build based on the E-tube platform and can be adjusted with the dedicated E-tube (project) software. E-tube is SHIMANO’s electronic shifting program where shifting functions can be customized. For example all the shift buttons can be individually programmed. Besides customization E-tube offers the possibility to upgrade components with firmware upgrades after its purchase.
This requires then SM-PCE1 PC Interface

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.

Note: The Ultegra Di2 products are not compatible with Dura Ace Di2.