Might be a dumb question but can I put a 183mm Hope rotor with an elixir caliper?
I would bet there's gonna be 2mm of brake pad not being used.... if the Elixer is set at 185.
You should probably use a Hope 183mm adapter.
Pivot Firebird, Tomac Snyper, KTM 250SX
It should work yeah, plenty of people i know use 183 floating rotors on avids even with the 185mm adapter.
I myself am using Hope "Pro" rotors 160mm which have a braking surface only 13.5mm wide - my avid pads are 15mm wide - yet the hope rotors work better than the stock avid ones.
For best results though just use the Hope 183mm adapter.