The chain on my road bike got caught in the rear cassette and as it snapped it broke one of the guide tabs on the inner cage plate of my new Shimano Ultegra 6800-SS rear derailleur. My two questions are:

  1. How safe is it riding with this cage plate, given that it's only a guide tab? A mechanic at my LBS said that I can keep riding for a while, as long as the chain doesn't jump over the cage when I downshift.

  2. Where can I get this cage plate without having to buy the entire derailleur?

    image of broken inner cage plate

  • 1
    For years derailleurs were built without the tab. If the chain is not too slack nothing will happen.
    – Carel
    Commented Jun 16, 2016 at 18:16
  • 1
    The tolerances on higher speeds are getting ridiculous. I'm not sure I'd risk it.
    – Batman
    Commented Jun 16, 2016 at 23:20
  • I discovered some more issues with my rear derailleur, and it's inexpensive relative to the effort to locate and purchase the inner plate, so I'm buying a new. Thanks for all the help.
    – Gingi
    Commented Jun 17, 2016 at 15:33

2 Answers 2


The relevant document is Shimano EV-RD-6800-3608A (Jun.-2013-3608A), which gives an exploded view and part numbers for each of the parts of the derailleur. For the Shimano Ultegra RD-6800 SS, you're looking for Shimano Y5XH08000 for the inner plate. (This also applies to many of Shimano's other parts to find replacement pieces)

Given that you've invested in Ultegra level gear, I'd not risk it and just wait for the replacement to arrive.


Bike shops will sell you a replacement. If you are in the UK then for example


  • Thanks. I actually asked my (US-based) LBS, an authorized Shimano dealer, and they couldn't find the part. They suggested I look for a used RD to grab the plate from there.
    – Gingi
    Commented Jun 16, 2016 at 21:03
  • Given that the rear derailleur is about 50 bucks total, I'd just get a new one instead if you're going to go down that route.
    – Batman
    Commented Jun 17, 2016 at 0:04
  • Thst's a good point, and I discovered other issues with the derailleur, so I am buying a new one. Thanks @Batman.
    – Gingi
    Commented Jun 17, 2016 at 15:34

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.