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 harms 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.
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. Because of the E-tube compatibility other shifting functions are available to Ultegra 6870 like Dura-Ace sprint and Roubaix shifters. In contrast to mechanical shifting, E-tube allows a rider to install multiple shifting options on a single bike.