I am on my second bike with Di2, for the first one I used some electrical tape where I needed to run the Di2 cables along the brake cable housing. It worked fine and it looked fine. I set up my second bike in a similar fashion, it is fine, but not great. The entry port of the Di2 cable on this frame is under the top tube, next to the brake cable stop at the front end of the top tube. As a result I need to run the Di2 wire along a much longer length of brake cable housing then my old frame (old frame had the entry port on the head tube, close to the front brake). I am running the 9000 Di2, so the cable is smaller than the 7900 Di2.
My question is what are some other ways to attach the cables together that look more clean than electrical tape? I am not sure if there are any specific commercial solutions for this purpose, if there is a solution designed for something else that people have used for this, or if some people smarter than I have some different ideas. I would love any advice or suggestions, even a photo if you have it. I like a clean looking bike and would like to find a better way to do this.