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I know I've had a nightmare with brake adaptors in the past.
Putting RX4 hope callipers on the road bike which has direct mount for 140mmm rotors.
Do Post-post adaptors just take the mount out along a radius?
The first mount on the shimano chart SM0MA90-F180 P/P I've used to take a 160 mount to 180 BUT it doesn't look like both ends are the same thickness.
Shimano PM-PM +20 adaptors that can be picked up for a lot half the price of Hope but they're generally marked 180mm (because pre road bikes PM was pretty much always 160 without an adaptor) eg ebay. and they're also frequently sold as 'front'
Hope list a different mount for post 140-160 (K) to post 160-180/180-200 (L)
but everywhere that's retailing it list K as specifically REAR post 140-160
I'd contact hope and get theirs.
On my MTB the hope disc rivets touched the shimano adapters. As well as not touching the hope adapter put the caliper in a slightly different orientation.
The Hope callipers don't clear the Shimano adaptors - a shame as they're smaller and lighter but no way they'll work.