I just replaced my front brake pads on my drz, and they went on just fine, had to push the pistons back a ways to get them to fit around the disc, but now when I'm riding it makes this high pitch whining/buzzing type noise, even when I'm not braking, but it does get a bit louder when I brake. I've heard this noise before when I would brake extremely hard with my old pads. Just wondering what it is and if there are any solutions to it?

noise coming from the brakes is caused by a vibration between two uneven surfaces. the problem is that your pads are new but the disk isn't. you need to go over the surface of the disk that the pads touch with a sander of some sort to give it a more uniform surface for the pads to "seat" in. a DA sander would do. sort of like honing a cylinder when replacing piston rings. then your brakes will stop the noise and you.