When you want to hammer a sprint like a Norse god (think Hushovd, not some mythical comic book hero), whether for the finish line, a money prime or the next road sign, the last thing you need is a slow or missed shift. Shimano Ultegra Di2 electronic shifting brings faster, effortless shifts at the touch of a finger. Mirroring Shimano’s top-of-the-line, race-proven Dura-Ace variant, the Ultegra Digital Integrated Intelligence shifters are about 5 oz heavier on the bike while being $1,700 lighter on your wallet, but offer the same features. While most of the pro racers at this year’s Dana Point, California Grand Prix criterium were sporting Dura-Ace Di2, Ultegra was more common amongst the amateur riders who actually have to buy their own schwag.
Gear changes occur with precision and a light touch — so light, it takes some getting use to — and the front derailleur auto-trims in sync with rear derailleur shifts, making dreaded chain rub a thing of the past. The 10-speed rear derailleur has a crash-saver function, allowing it to collapse inward if you lay it down, leaving you only a pound of flesh to replace. The lithium-ion battery is good for about 1,000 miles, with a handy indicator by the handlebars to signal recharging time, which takes about 90 minutes. The later arrival of the Ultegra benefits from lessons learned on the racing circuit, allowing a reduction from four wires down to only two. While road cyclists can immediately take advantage of the lower-priced model, time trialists and triathletes will still have to go with Dura-Ace.
Learn More: Here