So, because this is my first bike, and I still don't know all the mechanics of how parts work, I've been kind of paranoid of breakdowns. I got an '06 S-40, so it's still pretty new, and <5k miles on it. However today, I noticed that the throttle would just die on me, and my engine would turn off. My immediate thought was, "oh no, the petcock is failing. ahhhhhh!". So I remembered from reading some threads here, try turning to prime, and see if it runs better. I tried it, and well, my bike ran fine after that. Crap, I figured.
Well...tonight, while coming home, I noticed that my bike wasn't making any sloshing noise if I tilted it from side to side. TURNS OUT I WAS OUT OF GAS. Turning my petcock to prime worked because I was then using the reserve tank. Sigh.