E Tube length

Hey, I have a Specialized S Works with a Large frame and the original specialized cockpit

I am planning to put a Di2 on it with internal battery. I wanted to know what e tube length should I order.

Thanks,

Vince

Have you tried measuring?

I found this helpful:
http://service.specialized.com/collateral/ownersguide/new/assets/pdf/0000039491_R1.pdf
.

Thanks for that what cable to do I need for the cockpit for :

  • Shimano ST-6871 Ultegra Di2 STI Brake/Gear Lever for TT/Tri Bar
  • Shimano Dura-Ace Di2 SW-R671 TT/TRI Shifters

I have got the original S-Works frame cockpit.