Our top-of-the-line Shift I/O 9, is equipped with our new 160mm travel 4-Bar linkage frame, high-end Fox 36 Performance fork and Float X2 rear shock, Shimano XT Di2 shifting and an E8000 mid-motor drive combined with two different wheel sizes (for M to XL-sized frames) with a 29" front wheel and a 27.5" rear wheel for an unmatched riding feel. The shift I/O 9 with XT Di2 specs is sure to satisfy the inner tech geek in all of us with its capacity to fine-tune motor settings with its handlebar computer display and a downloadable E-Tube app for on-the-fly adjustment through a smart phone and a Bluetooth connection.