[Bow Tie 67]

I had something similar happen at Gingerman last year. Although my rotors and pads were well seasoned. Mark Stielow used a term, which I can not remember for life of me, and said it was build up of uneven pad material on the rotors. He suggested easy light braking to help re-bed the rotors correctly, eventually the pulsing went away.

Bedding in brakes is a process of depositing an even layer of brake pad onto your rotors. As the brake system is used the layer is, in flux, its constantly being removed and replaced.