Dura Ace DI2 sprintshifter AND top-bar-shifter

[philischen]

Saw that combi on some pro bikes:
both sprint shifter AND the shifter on the top of the bar

Anybody did that himself? Or has a plan how to do it?
John Degenkolb told me, that some japanese guys came over, did some soldering, done

Would be great to get some info. Thanks!!!

[irf3]

There might be a way to rig it up so you can have both. I'm pretty sure I read somewhere that it's a built in feature for the new di2 though.

[TurboKoo]

this combo is possible with new DA9070

[HammerTime2]

Are the top-bar-shifters for 9070 svelter (smaller, thinner, lighter) than for 7970? Why not use sprint shifters on bar-tops, with one on each side, with one side for rear upshifts and the other side for rear downshifts?

[philischen]

First of All, 9070 and 7970 are not compatible.
And actually, I don't want to buy a new group.

So on my 7970, I need to do some soldering.

The question is, what exactly I need to do...