While Shimano, Campagnolo, and SRAM have been offering electronic shifting for several years, FSA has now joined the fray, and SRAM has upgraded its eTap system to 12-speed and released the more affordable Force eTap. The cost of a complete electronic shifting bike is around £2,400, but should you consider making the switch?

 Improved Shifting

How much more precise is electronic shifting than mechanical? In a mechanical system, when you push the lever to move from one link to another, the front derailleur performs the same action every time. In an electronic system, the front derailleur's action differs slightly from that of the sprocket.

Let's take SRAM's eTap system as an example. When moving from a small link to a large link, the cage slightly overshifts to aid in chain jumping. Then, after a second, once the chain is on, the cage moves inward, returning to its standard position.

When moving from a large chainring to a small chainring, the cage moves inward in two stages. First, the shift is sufficient to move the chain down. Then, a second later, once the chain has dropped to the inner ring, it moves further, which helps prevent the chain from falling off the inside of the smaller link.

How much these two actions occur depends on the sprocket you're using at the time. Suppose your chain is on a small chainring and one of the larger sprockets, and you want to shift to the larger chainring. The rear derailleur tells the front derailleur that it needs to overshift more than if the chain were further out on one of the smaller sprockets.

The baseline is that you get good shifts even under load.

A Shimano representative said, "Dura-Ace and Ultegra Di2 electronic shifting precisely moves the chain to where it needs to be, past the programmed front or rear derailleur position."

"The science behind it is incredible, and it can even be programmed according to specific shifting preferences. Once you issue a command, the system reacts precisely every time. In a race, that reliability and confidence can mean the difference between a break and not breaking."

Faster Shifting

With a mechanical shifting system, if you want to shift across the entire cassette, you need to press the lever multiple times (the number of presses varies by system). With an electronic system, you can shift from one side of the cassette to the other by simply holding down the lever. It's much easier.

Campagnolo claims that "[EPS rear derailleurs'] shift time is 25% faster than mechanical rear derailleurs (0.352 seconds per sprocket change)."

No Chain Rub 

When a Shimano Di2 or Campagnolo EPS system is set up correctly, it automatically completes shifts in any sprocket, so there's no need to adjust the front derailleur's position to prevent chain rub on the front derailleur's side plate.

Easier Operation

Electronic systems require less lever movement than their mechanical counterparts to change gears. You simply press a button; there's no need to sweep a lever.

While moving a lever on a mechanical system isn't the most awkward operation in the world, if you want to shift across the entire range, this might be a minor point. With an electronic system, things are much easier.

With SRAM's eTap system, the lever on one shifter performs an upshift, and the lever on the other shifter performs a downshift, moving between chainrings simultaneously. This is a very simple system, even with large gloves or mittens in cold weather.

Customizable Shifting

With Shimano Di2, when you press and hold a lever, the system shifts. You can customize the shift speed and the number of gears. You can also swap the functions of the up and down levers, and even the left and right levers. SRAM's initial Red eTap system didn't have the ability to customize shifting, but these two new AXS 12-speed groups are customizable via a smartphone application.

Campagnolo's MyCampy application allows you to customize shifter functions on EPS systems.

Multiple Shifting Position Options

On road bikes with Shimano or SRAM electronic shifting, it's common to shift using the brake/shift lever combination, just like with mechanical systems, but you can also add satellite shifters elsewhere on the handlebars. In some cases, this makes shifting a bit easier, especially during races.

Shimano offers remote shifters that can be mounted on the top of the handlebars.

Minimal Maintenance

With electronic systems, there's less routine maintenance; you don't need to replace cables. After initial setup, there's very little need for optimization, if any.

Even with SRAM's eTap system, which is very easy to set up initially because it's wireless, there's no need to route cables through your frame.

Mechanical shifting has functioned well for many years and will continue to do so. It's also considerably cheaper than an electronic setup. If you don't find the benefits above compelling enough to switch to electronic, component manufacturers won't stop offering mechanical shifting anytime soon.

Why not try electronic shifting?