The Di2 Hydraulic STI shifters are out (STR785) and available for sale.

I have heard rumors that Shimano has a wireless system that they have been testing for a long time.

I sort of like the hyrbrid approach that FSA is taking. The FD and RD are wired together and have a single battery. The shifters are wireless to the connected derailleurs. That eliminates one system battery and one radio. The connection between FD and RD is a simple single wire so there is no need for junction boxes or other contacts. Contacts, batteries and radios are often a point of failure in an electronic system and eliminating as many as possible of each is a good thing.

With regards to using it, the SRAM system looks like from the GCN video that it works well in terms of shifting, shifting under load etc... I don't care for the ergonomics with respect to shifting the front derailleur where you need to actuate both shifters and then it toggles between the rings on the front. There have been many times where I have mistaken that I was in one ring or the other in the front and tried to shift and really not needed it to shift. In other words, I want to have certainty on which ring that I want to be on and not have it just toggle back and forth. Also, there are any number of times when I've needed to shift with just one hand on the bars (drinking, signalling etc...) so using two hands, while not a showstopper, would be aggravating.

Undoubtedly, wireless will be a big part of the electrics market. This will make converting an older bike from mech to elec a lot easier and cleaner. Today, with wired systems, it's kind of a mess.


J.