Shimano Ultegra R8170 Di2 Disc Groupset With technology trickling down from flagship Dura-Ace, Shimano's Ultegra R8170 Di2 Disc Groupset is better than it has ever been before. It perfectly balances performance with value, and the components are slick, reliable, and only create a minimal weight penalty compared to Dura-Ace. Shifting is flawless, and faster than previous iterations, while operating almost silently. This is thanks to Hyperglide+ tooth profiles, meaning that the chainrings and cassette have an improved connection with the chain, essentially improving shifting under load, across the cassette. Adding in a 12th sprocket, progression through the gears is smoother too. Braking is equally impressive, and redesigned calipers provide more clearance between rotor and pad, reducing rubbing and scraping noises frequently heard in wet or gritty conditions. Servo Wave levers, which have been redesigned for improved ergonomics, speed up the initial travel so pad and rotor meet sooner, creating a more progressive feel. Aesthetics are sleek, with the semi-wireless system eliminating wires from shifters to derailleurs. The battery remains mounted in the seatpost or seattube, and this is wired to the derailleurs, while the charge port is now incorporated into the rear derailleur, so there is no junction box required. CR1632 coin cell batteries in the shifters provide 1.5 to 2 years of life and easy access to the port on the rear mech makes charging the rest of the system easy. There are plenty of configurations to choose from, including various crank lengths and both mid-compact and compact chainrings, making this groupset a fantastic option for the majority of riders looking to upgrade their bike to an electronic system.  Includes Shimano Ultegra Di2 ST-R8170 hydraulic disc, Di2 E-tube STI set, flat mount calipers, left/rear and right/front Shimano Ultegra Di2 FC-R8100 12-speed double chainset Shimano CS-R7100 105 12-Speed Cassette 11 - 34T Shimano SLX/105 CN-M7100 chain with quick link, 12-speed, 126L Shimano Ultegra Di2 RD-R8150 12-speed rear derailleur, E-tube Shimano Ultegra Di2 FD-R8150 12-speed front derailleur E-tube, braze on, double RT-MT800 disc rotors with internal lockring, Ice Tech FREEZA, 160mm Di2 BT-DN300 internal mount battery, 3-port EW-EC300 battery charging cable, 1700mm This groupset excludes di2 cables and a bottom bracket. If you require assistance with this please contact us.