After all the research, prototypes, anticipation and debate over Shimano’s foray into electronic gear shifting, the lid was finally lifted in 2009 and out leapt the new, electronic DURA-ACE 7900 Di2. This groupset was the first to replace the age-old mechanical cable shifting layout with a wired electronic system, all powered via an external battery. It turned heads, but despite raising the bar in gear shift efficiency and precision, it had its technology sceptics too. Inevitably time would show the doubters and over the next few years this technology became rooted at the core of competitive cycling. Now, every pro team on Shimano uses Di2, helping drive a growing popularity among consumers too.