The new FD-R8050 has been redesigned and conceived for larger gaps between the chainrings without compromising shifting performance. Fast and smooth shifting in all conditions is guaranteed, even when shifting to the large chainring while riding in a standing position. With SHIMANO Synchro-Shift, the front derailleur shifts automatically when the rear derailleur is activated, allowing both to work efficiently together. Semi-Synchro-Shift works in reverse: the rear derailleur shifts automatically when the front derailleur is engaged, achieving optimal gear positioning front/rear. At the same time, the Auto-Trim feature of the Di2 automatically centers the front derailleur around the chain, minimizing chain drag while the chain moves across the cassette. This is how quickly, precisely, and smoothly your gear changes can occur.