Hurl Dissects Shimano’s Ultegra Di2

Words and photos by Hurl

Seeing UCI President Pat McQuaid in full kit, returning from a training ride in the beautiful surroundings of UCI’s headquarters in Aigle, Switzerland, I had to pinch myself to remember where I was, and why. Shimano had gathered several journalists for the official unveiling of their Ultegra Di2 electronic shifting platform. Well, I’m here to tell you that after just two days of riding in the Swiss Alps on Shimano’s Ultegra Di2, – along with dining on egregious amounts of fondue at a mountaintop restaurant, and, downing copious amounts of an incredible Swiss white wine and, yes, again, some insanely beautiful road rides in the area, I was sold on Di2’s quality, viability, and general worthiness.

While early adapters of push-button electronic shifting have been riding the spendier Dura-Ace Di2 for nearly four years, with advent of Ultegra Di2, Shimano has brought electronic shifting to the Broletariat. Is it better? That depends on one’s definition of “better.” It is cheaper, albeit slightly heavier, (250 grams more than Dura-Ace.) But, refinements to the wiring harness, ease of set up, greater adjustability, and most important, affordability, (Ultegra Di2’s cost is on par with Dura-Ace mechanical) may make Ultegra the defining electronic shift group of modern cycling.

Here’s why. At just 250 grams more than Dura-Ace Di2, but almost half the price, the Ultegra Di2 now uses just two wires, compared to Dura-Ace’s four, and with the seamless plug-and-play junction box, the whole system is waterproof the moment you plug it in. No more heating shrink tubing with a hair dryer is needed to seal the system. Two junction box options are available, internal or external. Ultegra’s internal cables are 5.1mm in diameter, decidedly smaller (and lighter) than Dura-Ace, and allow for a simpler, cleaner set-up. Internal wire noise has been greatly diminished with a simple clip-on cable tie system that holds the wires in place in the down tube. I still had some auxiliary noise on our Giant test bike, but this could also be partially attributed to the oversized carbon tubes.

Adjustability of the rear derailleur has been improved over Dura-Ace, and now has 15 micro-stops on either side of center, allowing for a total of 31 positions. You adjust this just once over any rear cog and the rear derailleur is instantly set and will never drop alignment. The rear derailleur also has a crash-saver function protecting the inner workings from impact if you do come off.

Battery life will last up to 3000km and is rated for 500 recharges. A battery indicator lets you know well in advance of when it’s time to recharge, and in the event that it does go, the front derailleur goes first as it takes the most energy.

So how does it feel? The shift feel is the same as Dura-Ace. According to Shimano’s Devin Walton, as with anything, the tighter tolerances of the higher-end group may lead it to maintain that “new-bike feel” longer, but unless you’re a Pro Tour rider or have spent copious amounts of time on the Dura Ace, you’d be hard-pressed to note any difference in the performance between the two groups. Shifting, as you might expect, is automatic and precise. While that is not exactly a surprise, the front shifting in particular, is so immediate and smooth. The front derailleur features an “auto-trim” function, said to eliminate all chain rub on the derailleur cage, even in cross-chain situations. This seems truly beneficial; especially to less experienced riders who’s form may not match their fitness.

On our second day we rode out from UCI HQ for a nice 4-hour ride, and soon found ourselves climbing some steep switchbacks. I experienced zero chain rub in any of the combinations that I resorted to, and was thankful for the 28T low cog on the cassette to haul my wheezing carcass up and over the col. Turning off onto a narrow, one-car lane we continued climbing, passing Swiss cows chomping on grass, and taking in views that just don’t occur for me in the Midwest. Soon, we were downshifting, descending to the base of the Champery Ski Resort, host to the UCI World Mountain Bike Championship. After regrouping, we downshifted again, and bombed back down the two-lane road into Aigle, reaching speeds upwards of 70kph.

These high-speed descents expose the one “drawback” to this system. You cannot “dump” multiple gears with a single throw of the lever, as you can with mechanical systems. Indeed, there are no “levers,” but rather, buttons. Just like clicking a mouse, each gearshift requires a single tap of the button. But it begs the question, is electronic shifting, “better?” Does it enhance the riding experience in any way? The answer may lie in one’s riding style, preferences, and hoped-for experience. If you’re a tech geek, and you derive pleasure from pumping max wattage into your crankset, being able to shift under load, then I’d say, yes, Di2 might be worth it.

Following our final “briefing” on the ins and outs of the sport’s governing body, we convened to the UCI’s in-house wine cellar, downing bottle after bottle of a fine white wine, from grapes indigenous to the Aigle region. Eventually, UCI Marketing and Events Director Gerrit Middag had to confirm that I wouldn’t be driving. I wasn’t. But I will need to make a return trip to Aigle for some of that wine, though. The bottle I stashed in my checked luggage was fully exploded when I landed. I’m just glad it wasn’t a red…

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