Ultegra Di2 on a 105 5800 groupset
Hi all,
I am thinking of getting a new road bike with a 105 5800 groupset. The frame has internal routing for upgrades. I was wondering if I wanted to upgrade this bike down the line with the Ultegra Di2, can I keep the current 105 11-28 cassette. Or do I need to swap it for the Ultegra version.