I think you will find the rotor damage is from not changing out your rear brake pad when it was time to. I have a rear Triumph rotor in my scrap pile off a T-100 from an acquaintance who bought his bike used, rode it and rode it, never even looked at his pads and had a complete rear brake failure in traffic on I-5 just as this post describes. Probably the first time he seriously used his front brake, ever. The description of the damaged rotor even fits.
