I don't know- I never burned all the way through a set of pads on a motorcycle. That said, all the motorcycle brakes I have experienced do make a 'hissing' sound with good pads.
It is easy to check the pads with a flashlight and without taking anything apart. You will have to maneuver your head and the light around a bit but you will be able to see the edges of the pads and there should be a gap between the steel backing plate of the pad and the rotor (the gap IS the pad material). Stock brakes have a groove in them that serves as a wear indicator- if you can see any of that groove, the pads are OK. You <might> need a small mirror to see all the pads but it is still quite easy.
I find motorcycle pads look dangerously worn when they are only 1/2 used up. They are thin to begin with, and appear even thinner when still inside the caliper. I have seen a lot of "worn out" pads that are less than 1/2 used up when compared with brand new pads. In fact, brand new pads look a little worn out to most of us. At least they are cheap, right?
Brian
Thx Brian, puts me at ease a bit...what about the noise? Is there a tell tale sign when pads are going bad?