97 Road King fuel injected will start and run fine when it is cold. After an hour or so of riding it will stall if I let off the throttle. I can keep it running by revving the engine, but if I release the throttle it will die. It won't restart immediately, but if I let it cool off it will. I did a fuel pressure test by connecting a fuel pressure gauge to the end of the hose that comes off the fuel pump and goes to the fuel filter. The result was when I first turn on the key, the fuel pressure jumps up to 60psi, but immediately begins to fall off. Within 15 minutes it is around 10psi. Could the fuel pump be losing pressure internally?