Believe.

At a time when electronic drivetrains are gaining unstoppable traction, we appreciate that Shimano chose not to neglect its storied pro-level mechanical drivetrain for Di2, making careful, meticulous updates that have resulted in subtle, but significant, improvements to functionality. For those of us who still unabashedly believe in the soul of mechanical shifting, the Dura-Ace RD-R9100 11-Speed Rear Derailleur feeds our love for self-actuated shifting with a more protected position and cleaner mounting interface.

When redesigning Dura-Ace, Shimano carried over the modifications to the rear derailleur shaping from Di2 to 9100. That involved altering the low-profile Shadow design slightly to better protect it in the event of a crash. This slimmer, more streamlined shape integrates expertly with the sleek aesthetics of the Dura-Ace 9100 drivetrain as a whole, delivering smoother lines and a less utilitarian appearance.

Shimano also worked to improve shifting efficiency on the rear derailleur, constructing the pulley to remain a consistent distance away from the cassette for more dependable shifts. The shorter, effortless shift throws on the levers result in crisp chain jumps up and down the cassette all day long with no sign of getting bogged down. Shimano also looked to its mountain drivetrains when reworking the rear derailleur's mount, adopting its Direct Mount interface to add stability and offer more efficient cage alignment.

  • Indulge in your love for impossibly crisp rear shifts
  • Sleeker shape allows for a more protected position
  • Redesign delivers clean, responsive shifts across the cassette
  • Direct Mount interface adds stability to the frame
  • Shimano indulges those of us who aren't ready to give up on mechanical shifting
  • Reviews
  • Q & A

The best!

  • Familiarity: I've used it several times

It is Shimano, Dura Ace, it is the best you can get. I'm using with 11 x 32 and works just perfect.

DURA-ACE RD-R9100 11-SPEED REAR DERAILLEUR

  • Familiarity: I've put it through the wringer

Okay I purchased this to update an R9000 derailleur. The derailleur cable routing was a little long with the R9000. With the R9000 I needed a wolf tooth extension to use 11-32 gears on my Zwift trainer. I have installed the R9100 and it is has the wolf tooth extension built in and it has a longer cage than the R9000. I have put it through the wringer on zwift with CVR world cups. I can use the full 11-32 including the 39-11 combo which I could not with the R9000. I will never use the 39-11 combo but the longer cage helps out a lot. What I have noticed is the shifting is considerably lighter and more precise that with the R9000. Also when climbing a steep short hill and switching to 53-32 momentarily; I don't get the grinding with the R9100, that I did with the R9000. The pulleys seem to be more smooth and the entire drivetrain is more quiet and precise.

I really didn't think that this upgrade would make that much of a difference, I just wanted the shorter cable routing for real life rides and races. But I have to say the upgrade to the R9100 is all that.

DURA-ACE RD-R9100 11-SPEED REAR DERAILLEUR

Super slick

    My god, this is lighter action than the newest Di2 shifters honestly. I sometimes don't even realize I have shifted! The new Shadow design means there is more chain wrap around the cogs for faster shifting. It also means easier wheel changes. Some people have said it was actually quite a bit more difficult to get their wheel out, so I was apprehensive before actually installing the stuff, but I found it marginally easier as the derailleur is tucked behind and out of the way. It also allows you to go up to an 11-30t cassette now, which definitely makes the difference after a long day in the saddle. The install is a little bit different than before, but at the end of the day its still just two limit screws, a barrel adjuster, and B-tension adjust. Nothing too dififcult if you know what you're doing. You will need a little piece of very flexible housing, either the included segment or a segmented system, like the Alligator iLinks I'm using.

    Another note is that it is compatible with all 11 speed Shimano shifters (5800, 6800, 9000, R8000, obviously R9100).

    Super slick
    Unanswered Question

    Is the 9100 rear derailleur compatible with 9000 shifters and 9000 front derailleur?

    Crisp and smooth shifting

      I upgraded from Ultegra to Dura-Ace and can tell the difference. crisp shifting and reliable.

      Unanswered Question

      is the shift actuation ratio the same as 9000?