Weight maybe? Contador's bike:
https://www.youtube.com/watch?v=5yqXIStXM4E
I thought Dura Ace DI2 was the lightest group set Shimano make? It's hard to believe that the cumulative weight of the cables adds up to the weight of the battery but I guess there are also all the mechanical internals to the hoods etc?
@ewanmac started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Weight maybe? Contador's bike:
https://www.youtube.com/watch?v=5yqXIStXM4E