I had a road tyre do this ( BT56s) on my ZX6r about two years ago (on a track day), again the concensous was that the track was hot /tyres pressures wrong ! Spoke to my tyre dealer & he said the pressure was prob wrong on the day !
Caused by to much heat from the engine,heating up the rear shock so losing all the damping. The extra heat from the engine was caused by the crank shells deciding to have a look around the inside of the crank cases
Did you use tyre warmers???, as it looks like cold tear, happens with warm tyres on a cold track & cold tyres on a hot track, if I am wrong I am sure some one of wiser knowlege will correct me
Tim, I think your tyres are sh@gged. Welll I found out what the problem was on the TZ-the rebound damping was 5, yes 5 (out of 20) clicks off the recommended setting, too dam soft.