I recently purchased a new carbon frame direct from a Chinese manufacturer (link to the particular frame here). The frame has BB86 bottom bracket. I am using the SRAM Press Fit GXP BB86 Bottom Bracket. Outside of the frame, the bearings seem to run smoothly when I move them around with my finger. However, once I press the cups into the frame, there is a significant grinding/drag present in the bearings. Here is a video that hopefully explains better what's going on.
I contacted the manufacturer of the frame, and they suggested that either the bottom bracket is broken, or has been pressed in "too hard". I'm relatively sure nothing is broken with the bottom bracket itself, since I purchased it brand new. I have also removed and reinstalled the bottom bracket several times with varying levels of force, with similar results. I am using the installation washers included with the Park Tool BBT-90.3 and a long threaded rod with two nuts on either end to install the bottom bracket. Any idea what's going on?