I didn't get my bike yet but it will have a Fox fork with post mount and I plan to swap over my xtr IS brakes that I took off of my Scalpel with a Lefty. The problem I think is that I have 160mm xtr center lock rotors and dont want to buy a 180 mm one. Does Shimano make an adapter that will allow me to use an IS Brake with a Post Mount and keep my 160mm rotor? I will be running dtswiss 240 15mm hubs that only come in center-lock that's why I wanted to stay with the center-lock rotors. From my search it looks like I will have to upgrade to a bigger rotor.