Motorcycle Safety & Driveability: Rotors or cuped front tire, bike speed, hand lever

Question
I have an 04 1200 Bandit, the bike has 7k on it when I apply the front brake at speed 60+ the front forks judder back and forth until the bike speed drops to 40 or so. I don't feel any pulsing in the front brake hand lever at all. The front tire has some cupping and thats why I am wondering if it is the rotor or the cup front tire I am feeling when the brake is applied.
thanks
 Dave

Answer
You know that sounds like it might be thr rotor because if it was the tire it would seem that this would happen even below 40mph.  I would maybe try getting a new pad in their and see if that helps.  If not then maybe take it to somone who would honestly know what they were looking for.