Gear Reviews

If you were riding a bike with Ultegra Di2 while blindfolded (which we don’t recommend), you would have no idea the drivetrain below you was Shimano’s newest entry into its electronic shifting lineup, and not the top-of-the-line Dura-Ace version. After introducing the Dura-Ace Di2 drivetrain two years ago, the Japanese powerhouse brand owns the market. Campagnolo is close to releasing its own electric drivetrain and had it on display at Interbike, but still hasn’t set a date when it will go on sale to the public. Chicago-based SRAM still hasn’t entered the game, and doesn’t seem particularly interested in doing so.

That leaves Shimano to compete with itself, and for 2012 it’s giving customers a second option with Ultegra Di2. Though heavier than the Dura-Ace version by about 260 g, Ultegra Di2 is around $1,760 cheaper than its counterpart, and has garnered a massive response from bike manufacturers who are desperate to offer Di2 versions of their road bikes for the coming season. Samples and demo drivetrains were a hot commodity, but in September, Canadian Cycling Magazine received one of the first sets of Di2 in the country for testing.

Changes from Dura-Ace Di2

Although Ultegra Di2 is a trickle down from the Dura-Ace version, this is also the second generation of the electronic drivetrain. As a result, Shimano engineers took what they learned from the original groupset and made improvements. The most noticeable change is in the wiring. The Ultegra wires are thinner than the first generation and use two ‘junction boxes’ - one is the battery indicator and control box and the second is a junction that goes under the bottom bracket. This makes installation easier and allows Di2 to be custom-fit onto more bikes. Unfortunately the wiring changes mean that the first and second generation of Di2 (between Dura-Ace and Ultegra) aren’t compatible. Also improved is the shape of the shifters for a more comfortable feel.

Installation

The thought of installing an electronic drivetrain is intimidating to many, but it’s easier and faster than mechanical. The next generation wiring kit with individual wires connecting into the bottom bracket junction box makes the install surprisingly simple. The shifters and derailleurs install just like mechanical components, except that instead of running cables and housing between them, you’re running wires. There’s also a battery mount to be installed, but it simply attaches under the bottle cage mounts. The most time spent on the install will be in tying down and hiding the wires for a clean look.

How it rides

As mentioned above, there’s no difference in the performance of Ultegra Di2 compared to the Dura-Ace version. Both drivetrains work incredibly well with effortless shifting regardless of the gear selection. Shifts under load are trouble free and no matter how fast you hit the buttons in an effort to confuse the system, it remains precise. Cross-chaining, or noise from the chain rubbing the front derailleur cage, is not an issue with electronic shifting because the front derailleur automatically adjusts itself as you shift through the rear cogs. Ultegra Di2 is watertight, so even when conditions are nasty, there’s no concern of failure. The lithium ion battery pack is the same as the Dura-Ace version and will last for around 2,000 km on a single charge (depending on the amount of shifts, of course). When needed, the battery recharges in around 90 minutes.

What’s the market

When Dura-Ace Di2 came out, we said it was an incredible drivetrain that worked great, but we felt the high price made it a bit exclusive. With Ultegra Di2, the price sits at just under $2,600 - the exact same MSRP as mechanical Dura-Ace. That means consumers will now have the choice - do you want the light weight of traditional Dura-Ace or the performance and cool-factor of Ultegra Di2. This is a drivetrain that appeals to a wide variety of riders - from cyclocross and road racers to smaller women who sometimes have trouble shifting gears to those who often ride in poor weather and don’t want to deal with the associated shifting issues. Because of the price, it makes electronic shifting a realistic option for more than those willing to spend $10,000 on a new bike.

Should you buy it?

As much as we loved Dura-Ace Di2, we had a hard time recommending people spend the money on it because it was so much more than a traditional drivetrain. That’s no longer an issue with Ultegra Di2. If you’re about to buy a bike that is offered in either a standard Dura-Ace drivetrain or Ultegra Di2, take the latter. The performance of electronic shifting can’t be matched and more than makes up for the 300 g weight penalty over mechanical Dura-Ace.

Here’s a breakdown of the weights and costs of Shimano’s top-end road groups. Total weight includes shifters, derailleurs, brakes, crankset, chain, cassette and wires or cables and housings.

Ultegra 6700 (Mechanical) - 2,402 g - $1,460

Ultegra Di2 (Electronic) - 2,482 g - $2,595

Dura-Ace 7900 (Mechanical) - 2,149 g - $2,595

Dura-Ace Di2 (Electronic) - 2,219 g - $4,355