Shimano has launched the first electronic groupset for mountain biking, the XTR Di2 (M9050). This development is the result of a very extensive testing program and is the moment many mountain bikers have long been waiting for. XTR Di2 comes in addition to the previously announced XTR M9000 mechanical groupset. The Di2 platform offers a number of advantages over a regular mechanical system including faster, more accurate and more powerful shifting which remains consistent in all riding conditions. Shifting requires minimal effort with a simple press of a button. XTR Di2 also brings a new programmable shifting layout called Synchro Shift. XTR Di2 offers a clean appearance on the bike and low maintenance thanks to the use of electrical wires.
Electronic shifting is not controlled by a regular mechanical shifter; it is controlled by a new electronic switch. Working with Shimano’s test riders and professional racers, Shimano engineers designed and tested many varieties of switches before the perfect solution was found. The result is Firebolt. An electronic shift switch that provides a natural feel, feedback and ergonomics. XTR’s easy to reach, compact shift switches offer a short stroke with tactile feedback.
One of the main advantages of electronic shifting is the programmability of the system. With new XTR Di2 it is possible to have the best shifting setup for every individual riding style. XTR Di2 works on the same E-tube platform as Shimano’s current road Di2 groupsets. The E-tube platform offers full programmability of the groupset and transmits interactive signals and power supply to each individual part by ‘plug & play’ connection. E-tube makes it possible to customise your shifting system by changing the function of the shift buttons. For example, it is possible to change the control of the front derailleur to the right switch and/or the control of your rear derailleur to the left switch. Multi shifting is also possible with XTR Di2 and is fully programmable. Multi shift can be engaged by pressing and holding the shift switch. Not only is the speed of the shift customisable but also the number of shifts, whether you want to shift up to a maximum of two sprockets with a single hold, or all the way through the cassette. Working with E-Tube electric wires also means no rust and no cable stretch while ensuring low maintenance and consistent shifting compared to a traditional mechanical cable-operated system.
One of the most unique features of XTR Di2 is the new Synchro Shift option. XTR Di2 has undergone over 20 000 test kilometres. This extensive test period allowed Shimano engineers to closely analyse the most used gears to be effective. With Synchro Shift enabled, it is possible to control both derailleurs with just one shifter. The front derailleur reads the position of the rear derailleur and automatically operates the front shift to position the gears in the most efficient gear and best chain line so the rider never has to worry about front shifting and correction shifts again. Synchro Shift is best explained in this video and improves efficiency of shifting and riding.
Shimano have used all the data from test riding to produce two pre-set shifting maps. E-tube allows the rider to change these pre-sets and create their own preferred shifting map. While riding it is possible to change between the programmed shifting maps or change back to manual mode. XTR Di2 provides fast and accurate shifting with less effort compared to mechanical systems.
Responsible for these shifts are the XTR Di2 derailleurs. These derailleurs deliver powerful, accurate and consistent shifting. The Di2 front derailleur is twice as powerful as the current M980 front derailleur and provides reliable, fast and smooth gear changes, even under heavy load. Shifting becomes effortless regardless of the terrain with a simple the push of a button. The rear derailleur is upgraded with new Shadow RD+ technology for Di2. Besides the regular on and off switch it is now also possible to externally adjust the spring tension of the rear derailleur with an Allen key (see video). The derailleurs react instantly to rider input and take up an accurate position in every gear combination using the front derailleur auto-trimming function. The electric wires guarantee stable and consistent performance.
Clean appearance and system expansion
The ‘brain’ of the XTR Di2 system is the digital display. This display indicates the battery level, gear position, shift mode (manual or Synchro) and the suspension mode. Using a button on the display it is also possible to change the shift mode to either manual or choose one of the two Synchro Shift maps, even while riding. The display also functions as a charging port, connection to the E-tube software (for personal settings) and includes 3 E-tube ports. Thanks to the E-tube platform, mountain bikes get a cleaner appearance. Electronic wires are easy to hide inside the frame and it is possible to integrate the Fox suspension system which minimises the visible cables on the bike and handlebars.
XTR Di2 M9050 uses the same batteries as its road equivalent. The external SM-BTR1 battery and the internal SM-BTR2 battery.