I ran a 1000cc GSXR in the A division at Road America July 7-8 and just chewed my tire up! I think it was the carousel but could there be something wrong. This was after 3 sessions! Pilot Race Rear
I ran a Pilot Race PRE on a fast Intermediate PACE and had no trouble with tire wear on my R1. I only ran Monday, but the tire looks ready to go again with no problem. The PRD is a pretty soft compound rear tire.
I'm going to say carosel and suspension setup - the chew marks are only on the right side Tire pressure may have had something to do with it too - what were you running? oh and did you have warmers on those?
That rear should be around 22psi... I am not expert, but that may be cold tear which means that you are running too much pressure (more pressure, less flex, less heat) Chad