How to customise Synchronized Shift settings

Updated January 6, 2021 by BetterShifting

Updated content available

An improved page on Synchronized Shift has been published. I'm not taking this older page down any time soon, but do recommend you read the new guide on Synchronized Shift instead.

Read the Complete Guide on Synchronized Shift

So you’ve read about synchronized shifting and are wondering how to set it up? Read all about customising your synchro-shift settings here. Note that you can also customise these settings using the mobile apps, if you have a Wireless Unit installed.

You’ll need a couple of things to get started. First download and install an up to date version of the Shimano e-Tube project software for your Windows. Then get your charger or pc-linkage/diagnostics device and connect your bike to your computer. Start the e-Tube application and connect to your bike. In the next screen, select the Shift Mode setting button.

e-tube home

After connecting, click the Shift mode setting button.

Shift settings

On this page you’ll be able to change the basic shifting settings. There are six options on this page. They are:

Synchro shift shift mode screen

  • Restore default values: resets all of the settings on this screen to their default value.
  • Number of teeth of FC: Use this to let the Di2 system know the number of teeth of your Front Chainrings. Setting this to the correct amount will make further customisation more accurate.
  • Number of teeth on CS: Set the range of your cassette. As above, this is required to make the information on the next screen accurate. Is your cassette not listed? Pick the best match.
  • Synchronized shift interval: Determine how fast the synchronized shift happens.
  • Shift mode 1: sets the mode the system will use when in shift mode one.
  • Shift mode 2: sets the mode the system will operate in when using shift mode two.

(There are 3 shift modes available: standard, mode 1, mode 2. You can customise mode 1 and mode 2. You can switch modes by pressing the button on your junction box)

Synchronized shift – gear ratios

Shimano allows you to customise how your synchronized shift operates. This screen shows you the current set up and lets you change it.

For semi-synchronized shift you can change the amount of rear shifts when you change gear at the front. The default ‘2‘ is usually good enough, but you can also set it to 1, 3 or 4 rear shifts per front shift. In this video reader Paul Teeter demonstrates semi-synchronized shifting with the number of shifts set to ‘3‘.

The synchronized shift settings are more interesting. Changing these settings in done through the ‘synchronized shift map’. Each cell in the map contains the gear ratio for that gear. The green and blue cells indicate the gear positions after which synchronized shifting is executed. Green cells and arrows apply to shifting up. The blue ones apply to shifting down.

Synchro shift map

Let’s follow the green arrow in the image above, starting all the way at the top left. When we’re in the lightest gear (28T/34T) and when we shift up we’ll eventually get to 14T/34T with a gear ratio of 2.43. If we shift up one more time the front derailleur will change chainring and the rear derailleur will shift down to arrive at 19T/50T (2.63).

Note that you can click either of the green cells in order to change the point at which the system shifts with which gear. We could make the system shift from 2.43 to 2.94 for example. This is why it’s important to set the correct chainring and cassette on the previous page – it guarantees that the gear ratios you’re setting up actually match the ones on your bike. You can customise both the blue and green arrows, of course!

My cassette is not listed – what to do

If you’re not using an Ultegra or DURA-ACE cassette chances are you cannot select your cassette range in the app. This is not ideal, but you can still set up synchronized shifting.

I suggest you pick the range that matches your cassette best. You then set up synchronized shifting as you would normally. Of course the number of teeth and gear ratios listed on the screen will be wrong, but the shifting points are correct.

What I'm trying to say is: if you set up your front derailleur to shift up when you reach the 3rd cassette cog it will do that, even if your 3rd cog doesn’t have the amount of teeth your Di2 system thinks it does.

Questions? Comments?

Did you manage to set up your synchronized shifting? Do you have any questions? Let me know!

If you're looking for roughly the same content in video form, have a look at GPLama's Di2 playlist.


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