By now you have probably at least heard about Shimano's Di2 (digital integrated intelligence), a shifting option to the company's proven mechanical shifting. But unless you've actually spent time on it, the important concepts of programmable electronic shifting may be hard to grasp. Instead of mechanical cables, Di2 is an electronic gear-shifting system that enables riders to execute shifts with electronic switches vs. mechanical shift levers. Through the use of Di2, shifts are fast and precise with countless customization options. The most important thing to remember as you watch these videos and read more is that the user is always in control of what your system does or can be pre-programmed to do. Whether you use a 1x11, 2x11 or even if you still love your 3x11 drivetrain, Di2 technology for mountain bikes gives riders from all disciplines and preferences the same core benefits.

Instant Response


Electronic signals between the shifter and the derailleur(s) give mountain bikers an instant connection to a wide range of gears, making it easier to react and stay in the flow of the trail. React instantly to sudden changes on the trail quickly and efficiently allowing you to save energy or find more speed. With Di2 you can pre-program the system to shift through your whole cassette by simply holding down the shifter. Or if you prefer a traditional approach, tap away every single shift. Additionally, there is no exposed mechanical cable and housing to add friction, be susceptible to contamination, or wear out. With Di2's electronic signals and its sealed system, shifts are powerful, dependable, and instantaneous.

What is Synchro Shift?


Synchro Shift is the kind of thing you don't completely understand until you try it. It gives riders the simplicity of 1x11 drivetrain, with the gear range and gear steps of a 2x11 drivetrain by utilizing a single gear shifter (or two shifters if you prefer) that can control both the front and rear derailleurs through programmable gear mapping.

Synchro Shift's advanced shifting technology allows you to program and execute multiple commands of your choice, with a single shifter. Not only do you choose when the front derailleur shifts, you can program simultaneous rear shifts to maintain cadence and momentum. However, if you'd like a left shifter, it can be used as well. It would allow you to manually execute a front shift whenever you wanted, but most riders don't find that necessary.

Synchro Shifting allows you to program and execute multiple commands with a single shifter.

Synchro Shifting allows you to program and execute multiple commands with a single shifter.​

Synchro shifting can be a great help for a wide range of people, but please don't just think of it as something for people who don't know how to use the gears on their bike. World class racers that are riding at the limit of their ability are often so far into oxygen debt that it becomes easy to make a mistake. Synchro shifting takes the possibility of rider error out of the equation when using a 2x11 system.

Of course, since its Di2, the Synchro gear map is fully customizable. There are even two Synchro modes which come out of the box tailored towards mashers or spinners. If you want to experiment you can make adjustments in the E-Tube Project software and switch between two settings on the trail to compare them.

Continue to page 2 to learn more about Shimano Di2 for mountain bikes »

Your gear should never be a limiter to where you ride your bike.

Your gear should never be a limiter to where you ride your bike.​

E-Tube Project

Here is a look into the customization options of Di2. If you have an internal battery charger, you already have the tool that you need to customize the way your Di2 bike works. Plug one end into the port on the handlebar gear display, and the other end into a computer USB port. The E-Tube Project customization software is available at www.shimano.com.

E-Tube project software can let you control several aspects of how the bike functions like which shift button does what, how quickly the bike shifts across multiple gears when you hold a button down, it can even let you turn a left shifter into a Fox iRD suspension control unit. In the Synchro Shift customization part of the software, you can adjust the default gear maps and make them your own.

You can even reverse shift direction. Maybe you have an injured right hand, so you can use a left shifter and have it control the rear derailleur instead. The great thing about E-tube Project and Di2 is the options and customization is endless and you can try and test to find an option that you maybe never even thought of.

E-tube software allows the rider to create specific shifting sequences for unique riding situations.

E-tube software allows the rider to create specific shifting sequences for unique riding situations.​

Most riders find that one of the two default maps are perfect without any changes. If that happens to be S2, you can move that map over to the S1 position and call it your normal Synchro Shift mode. Then S2 becomes available for you to create something special that you can easily switch to on the fly by double pressing that button on the gear display. Here are two examples for custom Synchro Shift maps:

Race Day:
The large chainring is a more efficient driving gear because of its larger diameter. The chain doesn't have to deflect as much in order to wrap around a larger gear. It's a small difference, but when seconds count, it can pay to maximize your driving efficiency.

A racing Synchro Shift map could have the bike shift back up to the big chainring as soon as possible after cresting a climb. That would mean that the bike would only use the two largest cogs on the cassette while riding on the small chainring. By the third shift, the bike would climb right back up to the more efficient chainring.

There are still 13 gear steps across the range, but now the most efficient gear combinations will take priority over a smooth shift up to the large ring. Just double press that button on the gear display on race day to switch over to race mode.

You might decide to avoid certain gear combinations when conditions are extreme.

You might decide to avoid certain gear combinations when conditions are extreme.​

Mud Riding: The 2x11 mountain bike groups are designed to be ridden fully cross-chained in the large chain ring, large cog combination without any trouble. However, in especially muddy conditions, you may find that the drivetrain makes a bit more noise in this big-big gear combination. A rainy day custom Synchro Shift map might not let the bike ever shift into the big-big gear combination. It would still have 13 gear steps across the entire range, it would just drop to the smaller chainring one gear earlier.

If you find yourself out on the trail in the rain, simply double press the button on the gear display and keep on riding. Options are endless. You are in control. E-Tube Project is the software that lets you customize your Di2 to exactly how you want it.

The Perfect Fit


With Di2, shifting is electronic. With this, Di2's shifters can be adjusted to a rider's unique grip and shift direction preference. Di2 levers can be micro adjusted to any rider's hand size. Custom ergonomics mean you can shift on the fly easier without having to adjust your grip on the handlebar. Additionally, through E-tube you can pre-program shift direction, speed and gear mapping. You decide as you have the ability to pre-program the shifter to do what you already do already. The decision and customization is completely up to you.