Harness the power.
This E-Tube Di2 Front Wire Harness kit is for Ultegra 6770 and Dura-Ace 9070 Di2 components. It features thinner, more discreet cables and a smaller junction than what you'll find on previous-generation Dura-Ace 7970 Di2 parts.
To outfit your Ultegra or Dura-Ace 9070 Di2 bike, you'll need five distinct wire sections -- front wire harness, downtube, front derailleur, rear derailleur, and battery. Unlike the other cables, this Front Wire Harness only comes in one length. It's the portion that connects the two shift levers to the A junction, which is included with this wire kit. And whether or not you run your other wires inside or outside the frame tubes, this is the part that is always nicely hidden underneath the handlebar tape.
- Q & A
Not compatible with DA 9070
- Familiarity: I returned this product before using it
While im sure this junction box works just fine, it will not work with 11s components anymore thanks to a firmware update from Shimano. If you can find some older 6870 or 9070 gear that was sold 1-2 years ago and has never been updated, there is a chance that it MIGHT work. This junction did work with a 6870 bike I have but would not work with a newer 9070 bike I was currently building. So yea...no longer 11s compatible unless you are mating it to older parts.
Outfitting my new frameset with Ultegra Di2 (6870).
Is this part applicable?
SHIMANO E-TUBE DI2 FRONT WIRE HARNESS (Item # SHI0393)
Or do I need to separately purchase SM-EW90-A and 2 EW-SD50 cables? If so, what size cables are normally used. I've got a 56 frame with 42 handlebars and a 110mm stem.