12-speed Front Derailleur installation and adjustment guide

Published January 24, 2022 by BetterShifting Terry, Last updated July 19, 2022

Installing the 12-speed DURA-ACE FD-R9250 and Ultegra FD-R8150 is easier than ever. Wireless connectivity comes standard on Di2 bikes now, and you can use the mobile app - E-Tube Cyclist to set up the front derailleur.

They don’t have any limit bolts, those are all set electronically. You do have to set the correct derailleur height and angle, however.

Let’s get right to it.

Tools and Preparation

The tools needed for installation are:

When there is a mounting boss on the frame

First, you’ll need to attach the front derailleur to the frame. How you do this depends on the frame itself. If your frame has a mounting boss, you take your size 5 hex wrench to loosely screw in the mounting bolt and attach the derailleur to the frame.

Tighten the bolt lightly - you’ll probably loosen it again later to fine-tune the height and angle.

These derailleurs have a tiny bolt that goes through the derailleur and comes out the back. You’ll later tighten this bolt to sit flush against the frame, giving the derailleur something to push against when shifting.

Now check where the derailleur’s support bolt hits the frame, and stick the support plate on the frame by peeling off the liner on the back. The support plate is the small metal plate you got with the front derailleur - it’s there to prevent damage to the frame itself.

Note that if the support bolt touches the frame’s mounting boss itself, you may not need the support plate. I haven’t used the support plate on my Cinelli, for example.

The support bolt should touch the side of the backup plate without the tape. Tighten the bolt until it touches the backup plate.

12-speed FD support plate

When there is no mounting boss on the frame

If the frame you’re using does not have a mounting boss you will need a Front-derailleur band adapter.

While you can probably get away with using any band adapter, I recommend using the one Shimano make, the SM-AD91 band adapter.

Install the band adapter to the front derailleur using a size 5 hex wrench and the provided bolt. You do not have to install the support plate, since you'll tighten the support bolt to sit flush against the clamp band. It won't damage your expensive frame.

Now tighten the derailleur’s support bolt using a size 2 hex wrench until it only just touches the clamp band. Remove the clamp bolt from the clamp band, attach the band to your frame and insert and tighten the clamp bolt. Do not tighten it fully yet, as we haven’t checked the height of the front derailleur yet.

12-speed FD clamp band and support bolt

Connect the electric wire

We’ll use the E-Tube Cyclist mobile app in the next step, so now is the time to connect the electric wire to the front derailleur.

If you haven’t installed the battery yet, I also recommend doing so now. Here’s a guide on installing a seatpost battery. When you read that guide, keep in mind that the 12-speed systems don’t use a Junction B - the guide was written for the 11-speed Di2 originally.

Once the battery has been installed, connect both the front derailleur, and the rear derailleur.

If you have two wires of different length, use the shorter of the two for the front derailleur.

12-speed FD wire and plug cover

Put the plug cover on the electric wire, and push it into the E-Tube port. You should feel and (usually) hear it click into place.

Don’t have the plug cover? Or lost yours? The front derailleur will work just fine without it - the prototype front derailleur that was on my media bike didn’t have this plug cover.

The cover does improve wire routing though, and therefore I’d definitely install it. Need to order a new one? The part number is Y2JP06000.

If you ever want to take the wire out, by the way, you can slide the TL-EW300 tool into the groove on the plug cover as shown in the image above. That should get you some extra leverage and help take the wire out.

Set the front derailleur height

To set the front derailleur height and angle, the crankset has to be installed. Do so if you haven’t already, and come back to this guide when you’ve completed installing the crankset.

The Shimano documentation doesn't explicitly state whether or not the front derailleur should be in the little or big ring, so it may not matter all that much. All the images show the front derailleur in the small ring at this point though, so that's what I tend to do myself.

Loosen the fixing screw

Loosen the front derailleur fixing screw using your size 5 hex key, and move the derailleur to the correct height.

12-speed FD installation height

Wondering what the correct height is? Take a look at the image above. Shift the FD so that it is above the largest chainring, and make sure there is about 1 to 3 mm between the front derailleur outer plate and the chainring.

Don’t tighten the fixing bolt right away, because you’ll also set the front derailleur angle now.

I’ll quote the Shimano dealer manual here, because it just makes sense:

Perform adjustment so that the flat surface of the outer plate is in a position directly above the largest chainring and that the rear edge of the outer plate is inwards by 0.5 - 1 mm compared to the front edge”

So, what does this mean? Basically, the front of the derailleur plate must be above the largest ring, while the rear edge is angled in 0.5 - 1mm.

front derailleur angled in

Now let’s straighten up the Front Derailleur so that the chain guide outer plates are in line with the chainring. Use a size 2 hex wrench to adjust the support bolt. It’ll push against the support plate (or clamp band), and push the derailleur out a bit.

Make sure that the flat portion of the chain guide outer plate is aligned with the surface of the largest chainring. If the support bolt does not touch the support plate, move the support plate so that it does.

Set up the support bolt to angle the derailleur back out

Limits - using the mobile app

Finally, let’s set the derailleur’s limits. Shimano’s 12-speed front derailleurs don’t have any limit bolts. There are two ways to set the limits.

You can either shift to the right combinations of gears in the correct order and set all three limits… or you can use the mobile app and let it guide you through the process.

Using the mobile app is a lot easier, less error-prone, and - since all 12-speed systems have wireless connectivity out of the box - that’s what I’ll use.

Feel free to look up the manual method in the Front Derailleur Dealer Manual (page 16) and set the limits that way.

This method is still useful for those of us without Android/iOS phones or tablets… but if you do have such a device, please just use E-Tube Cyclist. It is so much easier.

To get started, download E-Tube Cyclist:

Next, enable Bluetooth on your phone if it isn’t already, and start E-Tube Cyclist.

Locate the button on the rear derailleur and press it for 0.5 - 2 seconds. The LED will flash blue, indicating Bluetooth connection mode.

Now connect to the bike using the mobile app, or add the bike to the app, if this is your first time connecting to it.

E-Tube Cyclist home

Open the maintenance tab, and then, under Derailleur adjustment, select Front.

That’ll then take you to a screen that is a bit confusing. It tells you to shift to the gear combination displayed on the screen.

Don’t bother, you can’t.

Press Start, and it’ll perform the shifts for you. All you need to do is rotate the cranks.

The E-Tube App will shift to the right gear for you

Set the High limit

Now, we’ll set the high limit. You’ll do this twice, actually.

First, with the rear derailleur in the top position - the hardest gear.

E-Tube Cyclist: adjust the FD high limit

Now use the left and right arrows to adjust the gap between the chain and the front derailleur outer plate to 0.5 - 1.0 mm.

When it adjusts its position, the front derailleur will overrun slightly - and then move back to its final position. This is done to help you see the adjustment direction.

When checking the position of the chain and chain guide, do so after the derailleur has come to a complete stop.

Once you’re satisfied with the setting, tap Next.

The screen now asks you to move the rear derailleur to the low position - the largest sprocket.

It’ll perform the shifts for you, of course.

The E-Tube App will shift to the right gear for you

Now adjust the front derailleur’s top limit setting again, but severely cross-chained.

E-Tube Cyclist: adjust the FD high limit

This time around, set the distance between the chain and front derailleur to 0 - 0.5mm.

When you’re happy with the front derailleur position, use the Next button to go to the final step.

Set the low limit

You’ll see the screen below, indicating you’re getting ready to set the front derailleur low limit.

Tap start, and it’ll shift to the right gear automatically.

The E-Tube App will shift to the right gear for you

Again you’ll be asked to set the distance between the chain and front derailleur to 0 - 0.5mm.

Don’t worry - this isn’t a duplicate of the previous step. This time you’re setting the front derailleur’s low limit.

E-Tube Cyclist: adjust the FD low limit

Did that work? If you’re happy with your settings, use that Done button to complete the process.

You can now go through the app and change other settings if you like, or disconnect the bike and enjoy the ride. Just make sure you use the disconnect button. If you don’t, the bike won’t respond.

All done!

Your front derailleur should be adjusted perfectly now. If it isn’t though, keep in mind that you can repeat these steps any time you feel like it.

In case you're wondering - the derailleur has a total of 38 positions, as well as its neutral position. This means that it can move 19 steps in either direction.

Feel free to send me a message or just leave a comment if you’re having problems getting your derailleur to shift perfectly.

BetterShifting Terry

About the Author - BetterShifting Terry

I enjoy playing with bike tech - both bike building and wheel building, bike maintenance and of course, Di2. Besides writing content and working on the technical side of BetterShifting, I also work as a Software Developer in The Netherlands. Read more on the About this site page.

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