View from the Saddle: Electronic Shifting

View from the Saddle is a semi-regular feature where we discuss industry trends, technological innovations, or other interesting developments.

Introduction

We understand that electronic drivetrains are not exactly new on the scene, but we feel that it is necessary to write about them here in order to clarify certain issues that will come up once we start reviewing bikes. Simply put, we think they are great, but often not worth the extra money. So, rather than enter a lengthy discussion about electronic shifting every time we write a bike review, we can simply direct people to this article where we lay out the reasoning behind such judgements. Before you decry us as Luddites, know that we understand that electronic drivetrains work wonderfully, are here to stay, and definitely have their applications. Your road bike just isn't necessarily one of them.

Overview

Just a basic overview of the two systems on the market as of today.

Shimano Di2

First introduced in 2009 with the 7970 Dura Ace group. Shimano was not the first to develop electronic drivetrains, nor was it the first to market (a brief overview of electronic drivetrains in general can be found here). What Shimano was able to achieve was a product that was able to deliver the performance and reliability worthy of the Dura Ace (DA) name.

Reliability was especially important because this is something that had plagued earlier attempts. In 2011, Shimano introduced the 6770 Ultegra Di2 group. This was the first electronic drivetrain that was reasonably attainable to the average rider. It was not simply a lesser version of the original, as is the case with mechanical product lines, but in some ways it was better. The most obvious of these was the wiring harness was simplified and made more user friendly (no heat shrink tubing!)

In 2012, Shimano introduced the 9070 Di2 group, which made the jump to 11-speed. The Ultegra 6870 is due to be released for the 2014 model year. Each new iteration has offered incremental improvements, but nothing deviating too much from the original design. The DA 9070 was the first electronic group to be lighter that its mechanical counterpart.

Campagnolo EPS

Campagnolo’s foray into electronic shifting was a much later start than Shimano, but it wasted no time developing the technology down it’s range. Campy had been developing and testing electronic drivetrains as early as 2002 (or 1992 if you count the electronic/mechanical hybrid), but the first consumer ready group was the twin launch of the Super Record and Record EPS groups in 2011. In less that 8 months from that launch date, Campagnolo introduced the Athena EPS. In Less than a year, Campy went from zero to three electronic groupsets, leapfrogging Shimano in the process.

(Stayed tuned for a full Athena EPS review)

Advantages

To even its staunchest critics, the appeal of electronic shifting is apparent the instant you ride it. It just works. And does so quickly and efficiently. This is most obvious in the front shifting: a light touch gives a perfect shift, every time. The difference was definitely noticeable during Di2’s first generation, because their mechanical counterparts at the time (DA 7900 and Ultegra 6700) had arguably been a step back in terms of shift quality (blame it on the ‘under the bar’ cable routing). Today, the gap is much smaller, with the light and smooth action of the 9000 and 6800 group sets make front shifting as good as it has ever been.

Another nice feature of Di2 is the automatic trim function: the front derailleur follows the chain up and down the cassette to ensure that there is no rubbing. Shifting occurs faster as well. Campy claims that EPS shifts occur 26% quicker than mechanical versions. In addition, downshifting the entire cassette takes as little as 1.5 seconds!

Some of you may be thinking: “I know how to tune and shift my bike to have perfect shifts, without any chain rub. What is the point of all these motors? Don’t they just make bikes more complicated to work on at home?” While we agree with that statement in general, that is not true for everyone. Some people just want a bike that works every time without having to think too much about it. Not having to worry about contamination of unsealed mechanical systems and the increase in drag associated with the age of the cable and housing setup is a big benefit of an electronic drivetrain.

There is also the cost and labour savings by not having to replace that high end cable and housing yearly, or even more often for the high mileage riders. Also, a large portion of riders rely on their LBS for tune ups and repairs. For those people, as long as the extra cost up front cost isn’t an issue, electronic drivetrains are a perfect solution.

For those those among us that simply must have the latest and greatest technology, there is nothing better than an electronic drivetrain, except maybe electronic shifting with hydraulic disc brakes! The future is now!! (grin).

Another advantage of di2 especially is the extra shift buttons available to those who want a more customized cockpit. The Di2 Remote Climbing switch allows for shifting from the tops of the bars - a la Cancellara at Roubaix - as well as a sprinters option to allow easy shifting from the drops.

Disadvantages

For all of their benefits, there are a few disadvantages that go along with electronic shifting.

At their introduction, electronic groups carried a weight penalty over their mechanical siblings, around 100g for Di2 and 200g for EPS. To some this is pretty insignificant considering the performance, to others who insist on counting every gram, this is a deal breaker. Fortunately for those weight weenies out there, the latest Dura Ace 9070 is actually 24g lighter than mechanical. As time goes on and these systems continue to develop, we are sure that electronic systems will continue to get lighter.

Frame compatibility can be an added headache. Most current bikes are both electronic and mechanical ready, but upgrading your older model bike could be an issue if it is more than a few years old.

One of the biggest unknowns is long term reliability and durability. These products have only been on the market for a few years, so there is no way to predict what kind of useful life they will have. We do feel that these products will lean more towards the replace end of the spectrum, rather than repair. This would be an unfortunate side effect of the introduction of electronics into the world of cycling, and a dear departure from the principles that built the respective companies (Campy, and a lesser extent Shimano, is famous for having products that are serviceable for decades.) Hopefully we will be proven wrong on that point. On the other hand, the same could be said for the current mechanical groups as they too are unproven long term. Only time will tell.

We feel that value is one of the only categories that Di2 and EPS fail to deliver. Value is a very important factor to consider when evaluating any product or technology. These bikes do not exist in an economic vacuum, so there are always trade-offs. We pay for our parts, and so do the vast majority of cyclists out there. It is because of value that we can praise there will be times that we review a great product that we still cannot recommend on the basis of value.

Going by groupset MSRP, electronic shifting costs an extra $1100 for Di2, and $1200-1400 for EPS. By skipping electronic, you have a few options:

  1.     Save money,    
  2.     Upgrade to next level up (6870 and 9000 are almost the same price),        
  3.     Use the money saved for getting other bike stuff, like a good set of wheels.

We like option 3 the best. (grin)

Other Considerations

Many of the concerns that people had when these systems were introduced have been addressed by the later generations. Battery life has been a non-issue from the start, and programming software is now available to customize your system to your needs. Seat tube batteries help to clean up the installation and further weather protect the sensitive bits.

On a personal note, we find that we both consistently mix up the buttons on Di2 systems. While we are sure this would diminish if we were to ride Di2 more full time, this is not an issue when we change between the various mechanical systems (Red, Dura Ace, and Record). All of which used very different systems to perform the shift function. This may speak to the intuitiveness of the Di2 system, or perhaps the size/feel/placement of the buttons. We are happy to report that this did not occur with EPS, and probably has something to do with how much we enjoyed using it.

Not surprisingly, SRAM is looking to enter the market with an electronic drivetrain of its own. Two SRAM employees were spotted running advanced prototypes at the Midwest Regional cross championships in Chicago in December. Official details are scarce, but you can check out some speculation here.

Whether we want it or not, disc brakes are happening on road bikes, and hydraulics is a natural extension of that. Currently, the only way to run a full Shimano drivetrain with hydraulics is to have Di2. Having electronic shifting in their line-up significantly reduced the task of the engineers to find room for the master cylinder in the hood. We plan on covering hydraulic disc brakes in depth on a different instalment of this column.

The added shift buttons found on TT and triathlon bikes, offer greater versatility and safety. In addition, in the quest for greater aerodynamics, electronic cables can be run in patterns different from their traditional counterparts, an advantage that gives the builder/designer much more freedom to create the bike of their dreams. An excellent example of this is the striking TT bike Rob English built for himself. Notice the custom head-tube/steer-tube setup that allows for hidden cable routing.

Conclusion

There is a similar battle going on in the auto world today. Yes, today’s modern dual clutch automatic transmissions (such as the Porsche PDK) produce faster, more precise shifts that even the best driver, but some of us still like the feel of rowing our own gears.

As you can see, we are currently both hot and cold on Electronic drivetrains (mostly hot until we have to get out our wallets). And the best may be yet to come. As the great Lennard Zinn has recently pointed out, opinions are always changing and all of the advantages of electronic drivetrains may still not be known. Perhaps the concepts currently being pursued by Factor bikes gives us a glimpse of the future: total integration.

For the type of riding that we typically do, it is probably an unnecessary luxury. However, there are definitely here to stay, and as they develop and bikes evolve towards greater integration, there likely won’t be a top end bike without it.