Condensed Answer: The Di2 system introduces electronic shifting which eliminates a lot of the problems associated with standard derailleurs.
As a result, the rider is encouraged to shift more frequently. However, the group set is expensive and its purchase isn’t justified if other crucial components (e.g., the wheels) aren’t up to par.
What Are The Advantages Of Di2 E-Shifting
Electronic shifting either works or doesn’t. If the system is set correctly, it will shift the same way throughout the entire ride and will continue to do so for a very long time.
In different, mechanical shifting degrades with time and requires readjustments of the derailleurs, shifters, and shift cables to remain at the same level.
- Effortless Shifting Under Torque
Electronic shifting allows the rider to shift in imperfect conditions when mechanical shifting would fail. For example, it’s possible to shift even when the drivetrain is under torque.
This is one of the properties which encourage riders to shift more frequently and remain in optimal gear as much as possible. For that reason, one can argue that electronic shifting results in more efficient energy use.
- Lower Maintenance
A mechanical shifting system requires more maintenance due to the longer cables and their exposed sections. It’s quite possible for a cable to get stuck or contaminated. To avoid this issue, the user has to periodically clean or replace the cables if they’re worn.
An electronic system, on the other hand, works optimally with minimal if any intervention after the initial installation.
- Clean Look
If the frame is Di2-ready, the cables and the battery will be stored inside the tubes leaving the bike looking clean.
(But if the frame isn’t Di2-ready, the user will have to rely on an external kit. In that case, the cables are exposed.)
The Downsides of E-Shifting
Electronic shifting has only two notable downsides:
- Battery Dependence
The motors of the derailleurs require electricity and therefore batteries. If the battery isn’t charged, the rider cannot shift.
The charging cycles depend on how much one rides as well as the weather (batteries drain faster in cold conditions). That said, the batteries can last a long time.
A modern Di2 battery will last between 2000km/1242mi and 5000/3106mi per charge.
Therefore, even in the lower range, one will have to cover about 67km per day to burn through a battery in a month.
When you take into account the longevity of the battery, the recharging requirement doesn’t seem all that dramatic. After all, people charge their phones at least once a day.
The main downside of electronic group sets such as Di2 is the cost. In some cases, the purchase will reach about USD 1300.
When one takes into account that mechanical shifting is much more affordable and has performed just fine for many decades, it’s logical to conclude that e-shifting is a luxury.
Is Shifting Extremely Important?
Тhe transmission is a crucial component allowing the rider to cover more distance with less effort. Even the cheapest and simplest gear system (e.g., downtube shifters) offers a notable mechanical advantage over a single-speed bike.
However, eventually, one reaches the point of diminishing returns. For example, it would bе inaccurate to conclude that a rider using Shimano 105, for instance, does not have the potential to be as fast as someone equipped with Di2.
Shifting is important, but once a basic requirement is met, the benefits diminish. Consequently, many people make the rational choice to either save the money or invest it in another component. The most common choice would be the wheels.
Having a set of strong and yet light wheels is more beneficial than the luxury of electronic shifting. The wheels are always in use and can make or break a bike.
The Two Important Questions
Determining whether Di2 or another electronic group set is worth it comes down to two questions:
Are you willing to spend the money?
There is no denying that electronic shifting provides better performance than mechanical. The question is whether that performance is within the rider’s budget.
Spending USD 1300 on a shifting mechanism that’s more convenient but still practically performing the same task as a cheaper mechanical one is not always an easy choice.
It’s also worth mentioning that a bike on par with the Di2 system will cost a lot by itself. When you add the price of the groupset, you get a bicycle that could very well be over USD 3-5k.
While it’s awesome to have a top-of-the-line machine, pricey toys come with greater responsibility and the fear of losing them.
It goes without saying that installing a Di2 on a bike that will be locked outside even for 10 minutes is akin to leaving your wallet in the car without closing the door.
The ideal candidate for a Di2 or an equivalent electronic group set is an individual with the following characteristics:
- Sufficient budget to buy a Di2-ready bike + the group set without sacrificing a mortgage payment
- Performance-oriented cyclist (high desire to get maximum performance)
- Capable of minimizing bicycle theft (never leaving the bike locked; storing it inside)
Is the rest of the bike optimized?
Throwing a Di2 group set on a bike with a heavy frame and cheap wheels is akin to installing a Tesla transmission on a car from the 70s.
As already mentioned, electronic shifting makes a nice addition to a bike, but it doesn’t make the bike. It’s better to have an amazing frame and wheels coupled with an average group set than an average frame and wheels combined with an electronic wonder.
Thus, it’s necessary to examine the existing bike carefully before committing.
Summary: What You Need To Know
- Electronic shifting is more efficient and easier to maintain than a mechanical system. However, it’s not necessary for elite performance (many great riders didn’t have it back in the day).
- Electronic shifting adds a level of comfort that a dedicated cyclist with the needed funds for the upgrade could find appealing. In other words, if you want it and have the money, you will probably like it.
- Electronic shifting makes sense only when the rest of the bike is optimized too.