Aerodynamics / Aerodynamic Cost / Aero parts

Just found this on TTF forum by the TTGOD.

This is what I'll do. Hole in head tube behind steerer, cervelo don't seem to mind that, so will be fine. But I'll use the seatpost battery and hide it internally somewhere.

I've fitted Di2 to my P2. Just drilled one hole in the top of the head tube behind the steerer, used the existing exit hole near the BB. The only other mod was to enlarge the hole for the front mech cable, which doesn't prevent mechanical cabling still working in the future if required. You could easily enough route the front mech cable externally, though.

I used an adapter plate to move the bottle mount so that the battery would fit:
http://www.artscycle...-SHDI2BCBA.html
I routed the cable from the BB to the battery externally. It might be possible to put that cable into the frame through the same hole as the front mech cable, but then you'd need to drill another hole for it to exit near the battery. It could probably work quite nicely with the internal battery down the seat tube instead, you could probably get a cable to there via the hole that the front mech cable goes into.

It can be very difficult getting the Di2 cables through to where you want them. I ended up having to attach some cotton to a mechanical cable inner, then thread that cable inner through, which works okay as that is what the bike is designed for. Then detach the cotton and remove the cable inner, so you now have a length of cotton going all the way through the frame. Fasten the Di2 cable to the cotton and pull the Di2 cable through. The front mech cable was still tricky to pull through and took a lot of jiggling about, it doesn't seem to quite have a big enough gap inside the frame for it to travel through in a straight line, so there's a lot of luck in getting it to finally pull through.