I just replaced the brake pads on my front brakes of my motorcycle. The reason I did is because they made a squeeky noise. Not the typical brakepadmetal-on-metal-disk noise, but more similar to the noise you get when you rub the rim of a crystal glass1, but much much louder.
To my surprise, I think the brake pads were still in decent enough condition. I have attached some pictures. The scratches in these pads are due to me prying the pistons back with a screwdriver.
I checked the brake disk as well, and while it has a little wear (less than 1 mm), it looks nearly perfect.
My question now is, where did the squeeky noise come from? I had it a couple of times before, and it happens when I brake, when I'm nearly standing still. Last time I drove it, it happened every time I braked. So I quit riding it and replaced the pads.