Unanswered Adding RD-M8050 to EP8

[The Good Bike Doctor]

Hi everyone.

Trying to install an XT Di2 rear derailleur onto my EP8 equipped Merida eOne Sixty 700 bike.

Has anyone done this?? Or has a bike equipped with EP8 and a XT Di2 rear derailleur?

I have the following items:
XT Di2 Rear Der (RD-M8050-GS)
Shift Switch (SW-E7000_R)
Junction A (SM-EW90-B)
assorted Electric Wires (EW-SD50)

As far as I was aware, I was to unplug the Screen (SC-E7000), plug all the cables into the Junction A box and PRESTO!! But after plugging it into my PC-Etube box, it was that my Junction A isn't compatible. See below image

Information is limited online about setup. I think I read somewhere that I need to connect the rear derailleur straight into the motor, however all the 3 ports are already in use.

Any help would be great!

Cheers
Doug

 

[Zimmerframe]

Do you know why all three ports are in use ? There's the main one upto the top/display/box and one for the speed sensor, so there should be one free for the Di2. You'll also need to enable the motor for Di2.

 

[The Good Bike Doctor]

Do you know why all three ports are in use ? There's the main one upto the top/display/box and one for the speed sensor, so there should be one free for the Di2. You'll also need to enable the motor for Di2.

Yep.
One wire to the rear wheel speed sensor, another to the screen and the other to the power switch on the top tube.


Cheers

 

[Jojo10]

Hello

I did equipped my new Bullit last week with DI2 XTR
1. All three (small new) connectors on the motor are occupied. Like mentioned Sensor, Display, Switch!
2. The plug for the sensor is a special marked plug. It only fits at the motor, you cannot plug the sensor directly to the display.
3. So the derailleur needs to be connected to the display.
4. But! Why do I see only the old big plugs in your picture, not any new small ones, that are used for EP8 system
5. I have small connectors at my EP8 motor and also on my display. With fitting the DI2 I needed to mix connectors.
6. I did this without the expensive adapters by soldering the cables together coming from the motor to the display together with the cable from the derailleur.
7. You need to activate electronic shifting with the Apps. I did it with the EMax App. Maybe E-Tube App could do the same.

This setup works fine for me.

 

[mark.ai]

This is the compatibility chart for EP8:

I don't see that junction you have listed anywhere there (the SM-EW-90B) ...

Are you intentionally trying to get rid of the display? (Which is the normal junction A as listed in the chart above). I think you may only be able to do that by using the EW-EN100.

If you're not trying to get rid of the display then I think you should continue using your SC-E7000 as before, and not use that other junction box (which is not needed and not compatible).

 

[The Good Bike Doctor]

Hi all.

I'm not using the E7000 display, because I'll be running my Garmin as the display.

So this is the diagram of my possible fit.

There will be an EW-AD305 between the motor and SM-JC41.

Spoke to the guys at Shimano, and they say that looks good.

That Junction A box is the wrong one. I need the SM-JC41 instead.

Bike arrives in a few weeks, so fingers crossed it'll all fit!!

Cheers!