# Ultegra 6870 upgrade to BT or Ant+ for bike computer communication



## Terra72 (Aug 22, 2017)

I have a couple of months old Di2 Ultegra 6870 which I love - it just works. 

I am now looking to upgrade my bike computer and realise that some of the Garmin and Wahoo models can communicate with my Di2. It seems a shame not to take advantage of this option. Unfortunately, my current Di2 setup does not have Bluetooth or Ant+.

What is the simplest way to upgrade the Di2 to be compatible with either (or both) the Garmin and Wahoo bike computers?

The junction box is SM-EW90-B. The battery is internal inside the seat post (I am 99% confident that it is not the BT battery).

Many thanks, Erik


----------



## Marc (Jan 23, 2005)

You need either the EWW01 or EWW101 depending on which seatpost battery you have.

http://e-tubeproject.shimano.com/pdf/en/HM-CC.3.0.0-01-EN.pdf


----------



## MMsRepBike (Apr 1, 2014)

First know that there's very similar looking units with different functions.

First Shimano came out with a wireless unit that you could put anywhere inline in your Di2 system and it would talk to your computer with Ant+.


Recently they've decided to add bluetooth so you can use a phone app to tune things instead of a computer hard wired in. This has complicated things some.

They have a new wireless unit that's much like the old wireless unit, but this new one is both ant+ and bluetooth. But for this new unit to work right it needs a whole new battery too. So now there's two types of seatpost batteries, ones with and without bluetooth.


All you're asking about is Ant+. To talk to a Garmin, all you need is Ant+. Therefore all you need is one of the wireless units like this:










EWW01


If you want to go bluetooth, you'll need a new battery and new wireless units, so decide now.


----------



## rtalain (Dec 29, 2009)

MMsRepBike said:


> Recently they've decided to add bluetooth so you can use a phone app to tune things instead of a computer hard wired in.


In addition to this feature (which is pretty cool), the newer battery also allows the use of Shimano's synchronized shifting feature (SynchroShift). For me, this was worth upgrading my battery, although I also had to upgrade my wireless device. 

Ron


----------



## mjg57 (Apr 12, 2012)

I recently upgraded my 6870 to the newest firmware in an attempt to utilize the Synchro shift modes. I had an issue following the update and my system didn't work at all. After a long phone call with Shimano I was able to individually update firmware to my SMBR2 external battery mount and EW67A junction Box. The Shifters and Derailleurs were fine. The Shimano tech said I would need to upgrade the battery holder to a BM-DN100 (which I expected) and a new junction SM-EW90 (which I had not expected) if I wanted to use the new synchro shift modes. Additionally to talk with the new battery holder via bluetooth a wireless unit EW-WU101 would also be required. Synchro shift modes are getting very expensive. Can anyone comment if these item are required to access the new shift modes? Also, since the new junction box has three etube plugs and my shift cables are hard wired to my junction box I assume I'll need to run new cables for them as well. Any help or guidance would be appreciated.


----------



## rtalain (Dec 29, 2009)

mjg57 said:


> I recently upgraded my 6870 to the newest firmware in an attempt to utilize the Synchro shift modes. I had an issue following the update and my system didn't work at all. After a long phone call with Shimano I was able to individually update firmware to my SMBR2 external battery mount and EW67A junction Box. The Shifters and Derailleurs were fine. The Shimano tech said I would need to upgrade the battery holder to a BM-DN100 (which I expected) and a new junction SM-EW90 (which I had not expected) if I wanted to use the new synchro shift modes. Additionally to talk with the new battery holder via bluetooth a wireless unit EW-WU101 would also be required. Synchro shift modes are getting very expensive. Can anyone comment if these item are required to access the new shift modes? Also, since the new junction box has three etube plugs and my shift cables are hard wired to my junction box I assume I'll need to run new cables for them as well. Any help or guidance would be appreciated.


Battery holder upgrade: Yes (I have the internal battery, I assume you referenced the right part number)
Junction box upgrade: Yes (the SynchroShift status is displayed on the junction box)
Wireless unit upgrade: Only if you want to adjust your Di2 using your phone or tablet, or if you want to show the Di2 info on your Garmin.

Ron


----------

