Install 12-speed satellite shifters (EW-RS801)

Updated May 22, 2024 by BetterShifting Terry

Shimano 12-speed satellite shifters are tiny buttons or shifters that you can place in the drops, on the tops, or on your aero extensions. They only work when connected to a shift lever, and can not be used on their own.

All three variants are essentially the same unit and differ only in the wire length and mounting clips.

12-speed GRX / Ultegra / Dura-Ace shift levers required

These satellite shifters need to be connected to a shift lever. Either GRX, Ultegra (disc / rim brake) or Dura-Ace (disc / rim brake) shifters will do.


The 105 ST-R7170 shift lever does not have the required satellite shifter port, so that won’t work, unfortunately.

Buy the right shifter

Which satellite shifter you need depends on where you want to install them. Want to be able to shift from the drops? Then you need SW-RS801-S.

If you want to use these as climbing shifters, you’ll need SW-RS801-T. These have a longer wire and a larger diameter clamp band, allowing you to install it in the handlebar middle section.

TT/Tri bikes are a slightly different story. Shimano makes the SW-RS801-E, but its availability is relatively poor. It is expected to be in stock in November 2023, but who knows?

Want to add shifters to your clip-on aero bars? Then you can either wait for SW-RS801-E to be in stock, or you can use SW-RS801-S instead. These only come with a 100mm wire, but this wire can be extended to any length.

Want to know more? Read my guide on extending SW-RS801 satellite shifter wires.

You can also use the method described on that page to connect multiple satellite shifters to the same shift lever.

Install Sprint / Aero extension satellite shifters (RS801-S / RS801-E)

These two satellite shifters are the same unit, and the only difference is the wire length and the installation location.


In the box you’ll get:

  • The shift button
  • A 24mm diameter clamp
  • Adhesive tape

Place the satellite shifter on the handlebar

The very first thing you need to decide is where to install the switches. Sure, the sprint shifters go in the drops and the aero extension shifters go on the extensions, but the exact spot depends on your personal preference. Some people like their sprint shifters angled forward a bit, others want them to angle in, toward the rider.

Take the clamp and push it onto the shifter.


Then peel off one side of the adhesive tape and stick that onto the clamp/shifter.

If you’ve installed this shifter before on a different bike, don’t worry - any thin double-sided tape will do. The double-sided tape I used was 5cm long and about 0.5cm wide.

If you’re using your own double-sided tape, just stick it on the shifter and clamp, and use scissors to cut it to roughly the right size. It doesn’t need to be perfect, it’ll be hidden below the handlebar tape anyway.


You should now be able to push the shift unit onto the drops or clip-on aero bars without them coming apart. Before you do so though, plug the satellite shifter into the shift lever’s bottom port.

Doing so makes sure you don’t position it too far away from the shifter.

Line up the satellite shifter connector’s tabs with the little groove on the lever’s bottom port, and push it in. Using the TL-EW300 tool can make this easier.

Now decide on your shifter’s final position, peel off the remaining backing tape, and stick it on.

Depending on where you place yours, you’ll probably end up with a bit of excess wire. You can tape that to your handlebar as shown here.

See that little loop in the wire? It prevents you from pulling the wire loose accidentally.

If you’re not quite sure about the shifter position, just do a couple of test rides with only the satellite shifter installed - no handlebar tape. Play around with the position for a while and come back to this guide later.

Finishing tape/handlebar tape

With the satellite shifter in place, it’s time to wrap the handlebars. If you’ve installed them on your clip-on extensions, you can either add some tape to them or not - I’ll leave that up to you.

There are a couple of methods of wrapping the tape - I’ll describe two of those here.

Method 1: Cut an opening in a piece of tape

First up is the Shimano way. This involves cutting a hole in a (“cheater”) piece of handlebar tape, sticking the satellite shifter through that, and then wrapping the handlebar using the rest of the tape.

There are a couple of tools you can use to cut a hole. Shimano uses a knife in their documentation, but I prefer a (leather) hole punch or a regular hole punch.

leather hole punch, regular (paper) hole punch, knife

Using a cheater strip is a great method when using thin or weaker handlebar tape. It prevents the tape from tearing and breaking since the hole the shifter passes through isn’t in the main section of the tape.

I’m using red handlebar tape here since that’ll show the wires and satellite shifters better than if I were to use black tape. Also, I painted the handlebar white for exactly the same reason.

To get started, cut a piece of tape off, about 80mm in length.

Using a knife is straightforward, you just cut a 13mm x 9mm hole at one end of the piece of tape, about 1.5cm from the edge:

I cut the hole about 1.5cm from the edge

While a knife definitely works, I prefer using a hole punch. It’s a lot quicker, and looks better too!

I use the regular hole punch for regular handlebar tape, and the leather hole punch for tougher tapes - Supacaz for example.

Make sure the satellite shifter is in its final position, and then align the hole with the button:

You then wrap the handlebar tape as you normally would, and the cheater strip will hide the handlebar or aero extension as you wrap the tape around the satellite shifter.

Using a 13mm x 9mm cut hole. This area usually looks better when using a hole punch.

Method 2: no cheater tape

The Shimano method works fine, but the cheater strip placed underneath the handlebar tape can cause the satellite shifter area to grow thicker, effectively increasing the diameter of the handlebar. This is especially apparent when using heavily padded tape, or tougher tape.

I tend to use relatively strong handlebar tape myself, and I prefer to cut the hole in my main handlebar tape directly - without a separate cheater strip.

Be warned though. If you use this method, be aware that it is very easy to tear most handlebar tapes:

To do this, wrap the handlebar like you normally would. I prefer to wrap from the bottom, but if you like to wrap from the top - you can. It makes no difference.

Stop when you reach this point:

Now take a marker or pen and mark the spot where you want to make the cut.

Don’t pull the tape too tight as you do this - you’ll want to have a bit of wiggle room just in case the hole isn’t in exactly the right place.

This will happen, trust me.

With the location for the opening marked, take your tool of choice and punch a hole in the handlebar tape.

Continue wrapping the handlebar, and you’ll end up with something that looks like this:

It's much neater than cutting a square hole with a knife if you ask me!

Here’s another shot, as seen from the front:

Yes, those shifter hood covers have been removed _a lot_ and should be replaced. I know :)

Install Climbing satellite shifters (RS801-T)

The contents of the box are similar to that of the -S and -E satellite shifters. These climbing shifters come with a larger clamp band, and different adhesive tape to fit the clamp:

  • The shift button
  • A 31.8mm diameter clamp
  • Rubber strip
  • Zip ties / cable ties

Compared to installing the sprint shifters, setting up the climbing shifters is a bit more straightforward. You don’t need to make a hole in the bar tape, since these generally are not underneath the bar tape.

All you need to do is plug them in, tape the wire to the handlebar, and wrap the bar tape. Does your handlebar support internal cable routing? Even better!

Place the climbing shifter on the handlebar

While you can in theory place these shifters anywhere you like, they come with a 31.8mm clamp.

If you’re using a regular handlebar you can place them anywhere on the horizontal section of the handlebar. Aero handlebars generally only have a round 31.8mm section on both sides of the stem, and there’s not much choice in positioning these shifters on aero handlebars.

I’m using an aero handlebar here, so my climbing shifters will be right next to the stem.

Take the shifters, clamps, and thin black rubber sheets out of the paper bags if you haven’t already, and then place the clamp on the shifter:

When done, it’ll look like this:

Take the thin black rubber sheets and place them on the handlebar. One for each climbing shifter.

Now take the climbing shifter and clamp, and push it onto the handlebar, like so:

My handlebar supports internal routing, and the whole thing looks pretty neat.

Next, secure the shifter clamp to the handlebar using the provided cable ties.

Cut off the remaining part of the cable tie, and that’s it - the climbing shifter is now installed to the handlebar. All you need to do now is to plug it into the shift lever and you’re good to go:

Note: If you’ve lost your cable ties or simply need new ones because you’re swapping handlebars, the cable ties need to be at least 12cm long and no more than 2mm wide.

Questions, suggestions? Install multiple shifters

That's it - you can now enjoy your satellite shifters.

Do you know that you can extend Di2 satellite shifters and that you can also build your own satellite shifters? Definitely read those pages if that sounds interesting.

Any questions, suggestions, or problems you experienced installing your satellite shifters? Leave a message below, or send me a message.

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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