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Ultegra R8050 external (canyon ultimate)

ronthechefronthechef Posts: 943
edited April 2018 in Road general
I’m after some help/advice

I’m in the fortunate position of owning a canyon ultimate CF SL(non Di2) and I have ultegra R8050 shifters and mechs from another build that didn’t happen.

I’d like to use the R8050 bits with external cables, possibly the XTR battery holder rather than the older style external Di2 battery, is this possible? Also I think there is room to have the 2nd junction box inside the frame, (around BB area) has anybody done this? External battery and internal junction box?


  • ElfedElfed Posts: 459
    Hi, why do you want to use an external battery, can't you use the one designed for the seatpost? ... 8000857982
  • ElfedElfed Posts: 459
    I now get why the external battery but is there not a possible routing through the redundant cable ports under BB area up into the seat post?
  • ronthechefronthechef Posts: 943
    I didn’t think of that?
    What cables do I need to connect to the battery?
    Where would I route the cables? Handlebar junction, down the downtube(external), then up through the B.B. area to the battery?
    Thanks in advance
  • ElfedElfed Posts: 459
    ronthechef wrote:
    I didn’t think of that?
    What cables do I need to connect to the battery?
    Where would I route the cables? Handlebar junction, down the downtube(external), then up through the B.B. area to the battery?
    Thanks in advance

    I don't know which cables are required without doing a bit of research, sorry.

    On my bike I've the latest battery and the latest d fly unit, battery in seat post and d fly hidden in downtube behind headtube.
    The junction box is under the stem as my bars aren't compatible with the new bar end junction box.

    Have a look on the Weight Weenies forum, there's a wealth of information on that.
  • pilot_petepilot_pete Posts: 2,059
    You need;

    1. Junction box A, 3 port will do unless you want climb/ sprint shifters. This mounts under stem.
    2. 2 short cables (circa 350mm) to attach shifters, run under bar tape to emerge and fit to Junction A.
    3. 1 cable to run from Junction A down either outside your downtube, or inside through a suitable port, to your Junction box B.
    4. 1 cable to run from Junction B to front derailleur, 1 to run up to the battery in the seat tube and 1 to run to the rear derailleur.
    5. The later battery if you want Bluetooth options.

    Those are the minimum cables and junctions to get it all working. You can add in a Bluetooth sender which will require putting in line somewhere, so another cable will be needed. This will allow the system to talk to your Garmin via suitable pages and also to access the setup via eTube app on mobile device.

    You also need a charger which can also be used for diagnostics.

    If you are fitting to a non Di2 ready frame you will either need to mount cables externally or use suitable ports in the frame which will allow access to internally mount junction B and the associated cables. Normally Junction B can be fitted through the bottom bracket area (might need to remove bearing/ sleeve if you have one). Remember cables have attached plugs so any port needs to be big enough to pass the plug through, not just the cable. You may be able to modify a brake cable entry port by filing a small ‘u’ which is the diameter of the cable into its edge. You could then put the cable through, sit it in the ‘u’ and refit the brake cable. Fiddly yes and it does depend on whether you have metal guide ports in your brake cable port (assuming internal rear brake cable routing).

    Another option may be to get a carbon fibre repair specialist to drill suitable holes in your frame and reinforce them. That way you can have the holes exactly where you want them and if drilled the right size you can then fit specific di2 grommets.

  • ronthechefronthechef Posts: 943

    Thanks for a such a detailed reply.

    I’ll update the thread when I have completed the install
  • StillGoingStillGoing Posts: 5,207
    Although PP is correct, you don't need to run it that way if you use the bar end Junction A RS910. It may also work with the stem mounted Junction A. Di2 just needs cables connecting and it figures things out itself.

    You'd need the following:
    1 cable running from Junction A to the R shifter
    2 cable from R shifter to L shifter
    3 cable from L shifter to Junction B in the BB
    4 cables from Junction B to front and rear derailleurs and to battery

    If you want to fit blippers/sprint shifters, they just clip into the R8050 shifters so you don't need additional ports on Junction A. If you want to run D-Fly you will need the newer more powerful battery.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
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