Shimano Dura Ace 9070 electronic Di2 road groupset, now with the new internal seatpost battery
This groupset is rightfully leader of the pack, went together fine, check with the youtube tutorials. I need some frame specific grommets to finish the job, worth checking if you do too. Watch the tutorials about tie wraps on the long wire to stop any noise. Overall the parts are just immaculately engineered.
Fantastic group set and great price. Purchased for friend and he hasn't stopped raving about it. Easy to set up but please note that no instructions included. You can download off shimano site though. You will need a clamp if you do not have braze on mount on frame and the cable tidy strips are a must if external wiring set up is used. Kit comes with standard length cables and some of these were a bit too long but this can be expected with a small frame. You might want to change the lengths of some of them if you are anal about having excess cable wound in loops but it is bearable. Changing is silky smooth and quick. Set up of front and rear mech takes minutes. Make sure your wheels are 11speed compatible though.
It`s absolutely superb and much improved on the previous (also excellent) generation Di2. Looks better, lighter, easier to fit , more shift options, battery choice etc. If you can afford -BUY IT. One word of caution - if your fitting to a large or definitely to XL frame, you should consider 100mm longer cables for Rear mech, front mech and internal battery to junction box. Can be a tight fit otherwise
Ask any Porsche owner with paddle shifters if they would go back to a manual, you will get a resounding NO. Electric shifting is the future, and Dura-Ace Di2 is the King of the hill.
Shifting is precise, quiet and super easy to adjust. And never have to trim the front lets you concentrate on riding, not shifting, isn't that what it's all about. All this and no cable stretch.
Very easy installation and great price. I think the optional seat post battery is worth the extra cost. There is a definite improvement in brake performance when compared to 7900. Make sure your wheelset is 11 speed compatible.