During day three of Interbike 2014, I had a few moments to play with the Shimano XTR Di2 system. The system is officially known as Shimano XTR Di2 M9050, and continues the trend of Shimano’s naming standards. Simply put, the system is mind blowing! The shifter buttons offer the same tactile feedback you expect with the equivalent mechanical shifter, but with zero delay from button push, to derailleur actuation.
I didn’t try out the synchro mode of the system. Rather, I pushed the rear derailleur through it’s regular incremental steps, one click of the shifter after the other. The derailleur shifted as fast as I could push the buttons, or at a determined speed (customizable multi-shift) if I held down a shifter button. The front derailleur functioned flawlessly as expected.