• 08-05-2019
    XxJamesAxX
    Rear Derailleur Advice 1x set up
    Thanks in advance to any advise given.


    A good friend of mine is switching his road bike to a 1x set up to eliminate having to change gears in the front due to a hand injury.


    We currently have a shimano ultergra 11 speed shifter (drop shifter), a 11-42t rear cassette installed and have the front 1x chainring installed. 40t. We are now looking for a rear derailleur. Can anyone verify if this one will work:


    https://bike.shimano.com/en-US/produ...M9000-SGS.html


    My main concern is does the type of shifters make a difference when picking a derailleur? MTB shifters vs road bike drop shifters? As long as itís all shimano is it all compatible?


    Thanks again for any input you can provide.
  • 08-05-2019
    cxwrench
    Why don't you just use a bar-end shifter on the right side? No, the road shifters are not compatible w/ the mtb rear derailleurs, at least not 11 speed.
  • 08-05-2019
    XxJamesAxX
    Quote:

    Originally Posted by cxwrench View Post
    Why don't you just use a bar-end shifter on the right side? No, the road shifters are not compatible w/ the mtb rear derailleurs, at least not 11 speed.

    I guess it could be a option to go with the bar end but he just bought the new Ultegra 11 speed shifter so Iím sure he would prefer to use it. Anyone know if Shimano has a compatible derailleur with the set up Iíve described above?
  • 08-05-2019
    duriel
  • 08-05-2019
    cxwrench
    Quote:
    That does NOT work w/ the cassette the OP is intending on using.

    OP: I mean use the 11 speed shifter for the rear AND use the left side bar end shifter on the RIGHT side to control the front derailleur. Set up a bike like this for a para athlete I worked with a few years ago.
  • 08-05-2019
    jetdog9
    According to the Shimano compatibility lists, the only RDs that support 40-42 cog are in the new GRX line, BUT the Ultegra shifter isn't marked as compatible with those.

    https://productinfo.shimano.com/#/co...544&acid=C-255

    Edit: I don't know why they aren't listing other road shifters as compatible, maybe because they aren't differentiating just using the left shifter vs the right and all the other shifter sets are 2x. I would imagine the Ultegra right shifter will work fine since the RD-RX812 literature says it is road cassette compatible.

    Anyway, check out the GRX Series RD-RX812, might be your best bet.
  • 08-05-2019
    XxJamesAxX
    Quote:

    Originally Posted by cxwrench View Post
    That does NOT work w/ the cassette the OP is intending on using.

    OP: I mean use the 11 speed shifter for the rear AND use the left side bar end shifter on the RIGHT side to control the front derailleur. Set up a bike like this for a para athlete I worked with a few years ago.

    I was confused about what you meant at first but yea thatís a good idea. Fullishly I never even thought of that. Though I will add we are not bike mechanics. He brought up the idea of going to a 1x set up, we started playing around with bike gearing calculators online, figured out gearing that we thought would work and started ordering stuff to take to his local mechanic to install. Everything is now installed but the rear derailleur. At this point Iím hoping we can find one that will work but if not your bar end idea may be what we have to do.

    thanks again for all input
  • 08-06-2019
    XxJamesAxX
    We ordered the Shimano GRX RX812 as suggested. Iíll update the thread once itís all installed.
  • 08-06-2019
    cxwrench
    Quote:

    Originally Posted by XxJamesAxX View Post
    We ordered the Shimano GRX RX812 as suggested. Iíll update the thread once itís all installed.

    Have fun with that...according to the Shimano Compatibility chart the GRX 812 rear derailleur ONLY works w/ the ST-RX 810 and ST-RX 600 shifters.
  • 08-06-2019
    XxJamesAxX
    Quote:

    Originally Posted by cxwrench View Post
    Have fun with that...according to the Shimano Compatibility chart the GRX 812 rear derailleur ONLY works w/ the ST-RX 810 and ST-RX 600 shifters.

    I guess we shall see, I found multiple sources that claimed " It is compatible with current road dual control lever shifters so upgrading is simple." including Shimano's website.

    https://bike.shimano.com/en-AU/product/component/grx-11-speed/RD-RX812.html


    Maybe I'm misinterpreting that line but fingers crossed.

    I hope to have a update next week.

  • 08-06-2019
    jetdog9
    I'm hoping it works out for OP and friend. If the RD is meant to work with road cassettes, how could it not? I still think they did the compatibility chart the way it is because they list the shifters as sets and there's no reason to have a 2-speed right shifter (such as 6800 or R8000) with the GRX line in general.

    If it doesn't work, sorry for the suggestion.

    Edit: Oh, I see there is 2x for the GRX line. I forgot about that. Anyway, fingers crossed for you.
  • 08-12-2019
    XxJamesAxX
    Happy to report the Derailleur works perfectly with the Ultegra shifter. The mechanic said installing/tuning was no issue.

    Thanks again for all input given.


    Sent from my iPhone using Tapatalk
  • 08-12-2019
    cxwrench
    Good to know...now that I think about it I can't understand why Shimano would make those so shifters non-compatible w/ Ultegra, I was just going by their chart.