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Worn out 9 speed xtr shadow rear mech. Could anyone recommend a good replacement?

The outer plate of my mech broke away and to be honest the mech is worn out. I have a 9 speed mtb and finding it more difficult to find replacement parts. I would love to replace it with like for like but cant seem to find what i need. Would anyone recommend a good replacement rear mech if xtr is not available? I seen a xt deore available? Any advice would be appreciated. TY

Posts

  • navrig2navrig2 Posts: 1,633
    I am pretty sure I have:
    Brand new, never fitted, 9 speed long cage rear derailleur. RD 571 model.

    Problem is I am not in the UK and the derailleur is buried in my spare parts box in the garage in Scotland. I have some photos. I'll see if I can find them.
  • navrig2navrig2 Posts: 1,633



  • navrig2navrig2 Posts: 1,633
    Where are you?
  • steve_sordysteve_sordy Posts: 2,239
    Why not fit a 10-speed rear mech? The mech moves under instruction from the shifter. The fact that it moves in 9 steps from low to high instead of 10 is irrelevant to the mech.

    It could be part of a strategy to move towards 10-speed as components wear out. If the mech is knackered then the shifter may not be far behind.

    My lingering concern is that the 9-speed chain may not pass smoothly through the cage of the 10-speed mech. It should do so without problem, but it not called a 10-speed mech for nothing!

    This post may smoke out someone who knows for certain. But if you just cannot get a 9-speed mech........
  • steve9uksteve9uk Posts: 123
    Thanks Steve. Never thought of introducing a 10 speed mech. I'll look into that.
    navrig2 said:

    Where are you?

    Hi Navrig im in Newcastle upon tyne
    Many thanks
  • whyamiherewhyamihere Posts: 7,465
    edited March 2020

    Why not fit a 10-speed rear mech? The mech moves under instruction from the shifter. The fact that it moves in 9 steps from low to high instead of 10 is irrelevant to the mech.

    The bolded bit simply isn't true, and a 10 speed mech will not work on a 9 speed drivetrain.

    Shifters and mechs both have a specified pull ratio. This is basically the amount a mech moves given a certain amount of cable movement. These need to match, because the shifter will pull a set amount of cable, and the mech needs to move the right distance.

    The pull ratio for Shimano 9 speed MTB was 1.7. This was also the ratio for 6, 7, 8 speed and 10 speed road. So way back in time when people were upgrading from 8 speed to 9 speed, your statement was correct. However, 10 speed MTB changed the pull ratio to 1.2, which officially doesn't work with anything else. The pull ratio was changed again for the move to 11 speed, but this change was small enough that some people were able to get 11 speed mechs to work on 10 speed drivetrains, but the shifting wouldn't have been perfect.
  • navrig2navrig2 Posts: 1,633
    steve9uk said:

    Thanks Steve. Never thought of introducing a 10 speed mech. I'll look into that.

    navrig2 said:

    Where are you?

    Hi Navrig im in Newcastle upon tyne
    Many thanks
    My home is Dunbar so not too far away. If you are interested I can ask my wife to look for the derailleur. I appreciate it is Deore but, then again, it has never been on a bike.

    Let me know if you are interested.
  • steve_sordysteve_sordy Posts: 2,239


    The bolded bit simply isn't true, and a 10 speed mech will not work on a 9 speed drivetrain.

    Shifters and mechs both have a specified pull ratio. This is basically the amount a mech moves given a certain amount of cable movement. These need to match, because the shifter will pull a set amount of cable, and the mech needs to move the right distance.

    The pull ratio for Shimano 9 speed MTB was 1.7. This was also the ratio for 6, 7, 8 speed and 10 speed road. So way back in time when people were upgrading from 8 speed to 9 speed, your statement was correct. However, 10 speed MTB changed the pull ratio to 1.2, which officially doesn't work with anything else. The pull ratio was changed again for the move to 11 speed, but this change was small enough that some people were able to get 11 speed mechs to work on 10 speed drivetrains, but the shifting wouldn't have been perfect.

    Now that is the sort of detailed knowledge I was hoping might get smoked out! Brilliant!
    Every day is a learning day!! :)
  • navrig2navrig2 Posts: 1,633
    To the OP - I don't frequent the MTB forum very often (I am roadie mostly). I am assuming that you are NOT interested in the derailleur and will not return to this thread. If you decide you are interested then you will have to send me a PM.
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