I have the hope M4 with Pro Open Levers. The front is rock solid but the rear is pretty mushy. I've bled the darn thing a few times already but I just can't get the lever to feel right. I'm following the directions on hope's tech manual, and I think I've done everything right. Does anyone have any other tips or things I should watch out for? does the caliper need to be oriented in any specific way? Can the mushiness be caused by sticky pistons?