The Shimano Dura-Ace Di2 EW-7970 rear wire kit connects the battery to the front and rear derailleur and the front wire kit all sold separately. Centrally located is the battery mount which has a strip that mounts under the down tube bottle cage and sits directly below it so you can still have a bottle cage and the battery has a low center of gravity. The derailleur wires then pass through a mount on the bottom of the bottom bracket shell and to the derailleurs. Another wire runs up the dow…