Shifter Shimano DURA-ACE Di2 ST-R9170 2-speed

The hydraulic SHIMANO DURA-ACE Di2 ST-R9170 Dual Control lever for front 2-speed derailleur feature a refined hood shape with svelte shared ergonomics for more rider control in race conditions, which is expanded by an optimally balanced hydraulic brake system. The ergonomically-enhanced Di2 shift levers produce a more defined shift click for a more intuitive feel and quicker shifting operation and expanded E-Tube customization allows every switch the option to independently turn on or off multi-shift. Thanks to the customizable function the levers fit any riding style and the carbon composite plastic hood material drops the weight of the whole construction. Weight: 160 gDUAL CONTROL LEVER2 E-tube portsFirmware update by E-TUBE ProjectRecommended brake fluid: SHIMANO Mineral OilFree stroke adjust - distance from initial lever position to pad contact point can be adjusted to suit any hand size, type of riding and individual rider preferences.Funnel bleedingReach adjustInner clamp diameter: 23.8-24.2 mmBrake lever is equipped with a reach adjust mechanism. The distance from handlebar grip to lever can be adjusted to suit any hand size, type of riding and individual rider preferences.SEIS - innovative shift technology 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. This electronic shifting system has been extensively tested over past two years by several professional riders in all conditions possible, such as rain, mud, low temperatures, cobble stone roads and combinations of all of these at the same time. Shifting is executed by simply pressing the button. No power is needed to shift, which gives important advantages since it is easier now to always keep a tight grip on the handlebar and to keep your concentration on riding instead on shifting. The shift system allows accurate and effortless shifting in difficult circumstances for example when you have cold hands or when you are completely exhausted. Furthermore, the shifting performance will never be affected by contaminated or stretched cables since the shifting signal is transferred electronically. The operating buttons work similarly to mechanical DUAL CONTROL LEVER so you don’t need to re-program your mind for the SEIS.Di2 - 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. Important: All Shimano Di2 electronic components require the same firmware version. In order to diagnose, read or update firmware, optional device is needed. Operating components with different firmware version may cause malfunction or loss of function.