Originally Posted by
fietsbob
try a Sram MTB RD.
get it at your favorite bike shop to be safe ..
Unfortunately, that doesn't work for 11 speed SRAM. Their 10 speed stuff was cross-compatible (all Exact Actuation shift ratio), but their 11 speed MTB mechs now have a new shift ratio (X-actuation).
Hmm, though an 11 speed road shifter SHOULD index 11 speeds fine with a 10 speed Exact Actuation MTB derailleur. I've never tried it, but that's how Shimano's cross-compatiblity works (10 speed STI with 9 speed MTB RD).
Sounds like the OP found the proper medium-cage RD anyway.