All parts for the installation bought on ebay. To my luck the kit included the internal junction box and cables but with the external battery mount. Cable lengths were also strange as I got two 950mm, one 650mm, one 300mm and two 250mm. But it turned out to be great as one of the 950mm cable can be used also when I chnge to the internal battery.
Made some nice progres today on the installation. I can't complete it as I'm waiting for a set of Alligator I-link brake cables.
The holes for the grommets must be 6mm for them to fit properly.
As the plastic strips are rather stiff you need a stiff wire to guide it down the down tube. Then you just stuff it down helping the strips entering the hole.
The end of the cable will seek to the outside of the tube. Try rotating the guide wire to get it close to the hole. When close enough borrow your wifes thing here to pull it out. I don't know the name for it in english
In the headtube the cable is fixated in both end with hot glue.
My solution to routing the FD cable. I find it much cleaner looking than routing it on the front of the tube.
As I will initially use the external battery and are routing the RD cable externally both of these cable needs to go into the BB. I have chosen to use the hole for the FD guide, but you need to drill it up to 7mm for the cables to get in there. You need to push a bit as it's tight. The battery cable is 950mm so it's the right length for the internal battery.
The hole from the BB to the down tube is very close to letting the junction box through. A bit of chamfering on the edges did the trick.
When you get all the cables routed and connected to the junctions box it's a tight fit to get it in. Yo need to remove one bearing and insert the junction box from that side or you wont be able to rotate it into place. The cable connected besides the down tube cable in the junction box needs to pass the junction box when you push it through the hole so be sure you don't pinch it.
Trim the length of the cable and stuff the excess into the tubes. Then use hot melting glue to seat the cables so that it doesn't interfere with the axel when inserted.
Here is how the FD cable routing looks like. Much cleaner than the original routing.
The top tube cable routing.
The result so far missing brake cables and bar tape. The Ultegra grey blends nicely in with the frame graphics making the large component seem smaller.