Will Sram GX Eagle grip shift trigger work with 11sp cassette?
Unfortunately it will not work due to the cassette spacing, even using an 12 speed shifter and derailleur, it will not shift correctly due to the increased space of the 11sp cassette which has 3.8mm between cogs while the 12sp cassette has 3.65mm between cogs.


  [For a 12sp cassette] The spacing between cogs has been reduced, from 3.8 mm to 3.65 mm, and the 50 tooth cog cups the drive body more, thus bringing it closer to the spokes
  
  ....The shifter had to be redesigned to provide for 12 clicks and to incorporate revised cable pull to deal with the narrower cog spacing.


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