In this case, Shimano went off book with their DI2 groupset, leaving [kwakeham] with a reverse engineering job on his hands. [kwakeham] gives us a great example of how to approach reverse engineering.
Find out more about how we test. As I write this, Shimano Dura-Ace is sitting in the number one place in our best road bike groupsets buyers guide. We have it listed as the best road bike groupset ...