Rear derailleur Shimano DURA-ACE Di2 RD-R9250-E 12-speed

The Shimano DURA-ACE RD-R9250 12-speed rear derailleur combines charging port and wireless system in one compact unit to provide a lightning-fast and precise shifting performance that is ready to win. With just one cage length, the rear derailleur shifts on cassettes from 11-28T to 11-34T, further enhancing the versatility of the world's best road bike component group. THE SCIENCE OF SPEED: Shimano DURA-ACE Di2 12-speed Rear Derailleur RD-R9250. Shimano has been working for years to provide you with an advantage of seconds. 12-speed DURA-ACE R9200 is the fastest groupset ever and the pinnacle of SHIMANO technology and innovation. Speed was the key driver for the development of this generation road groupset. That's why every component has been revised, refined and optimised to make you even faster - whether to leave the peloton behind you or to win the final sprint on the Champs-Élysées.

TECHNOLOGIES

SHADOW RD – the mechanism rear derailleur, SHIMANO SHADOW RD, is intended for more aggressive riding. Its super low profile design carries many benefits. Because of its low profile and single tension construction, the derailleur does not hit the chain stay in rough riding conditions. The result is smooth and silent performance.

SEIS SHIMANO ELECTRONIC INTELLIGENT SYSTEM – The SEIS innovative shift technology is still 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 like 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 Levers so you don’t need to re-program your mind for a system.

E-TUBE – platform offers optimum flexibility on your bike. E-TUBE transmits interactive signals and power supply to each parts by “Plug and play” connection. E-TUBE is no rust, no stretch, no freeze and it ensures advanced low maintenance. And SM-PCE1 connects between PC and components to update firmware. Digital device stay the latest version with updating firmware for improve function.