Absolutely no electronics, battery/fuses/ground points are fine
 

The other day I started up my 2008 CBR 125R. After a few seconds of warming up, the engine shut off by itself. Okay, nothing too strange, it was kinda cold maybe it was just that. I go to start it up again, and it won't start.

I turn the key off and back on again, the headlights and the neutral light comes on, but no fuel injector light and the fuel injector didn't make it's usual whirring sound like it always does when you turn the key on. I hit the starter button and everything shuts off. No headlight, no neutral light, the bike is completely dead. I shut the key off, turn it on, and the same thing happens. I keep trying, and eventually when I turn the key on no lights come on at all even before I hit the starter button. If I rocked the kill switch on and off a bunch the lights would come back on, but again no fuel injector light or whirring sound, and it dies as soon as I hit the start button.

Eventually, after a few more tries, the bike is even more dead. Turn the key on, and nothing comes on, and the kill switch rocking won't bring the lights on. It's acting as if the battery isn't even connected now, even though it is, it's charged, and the fuses and ground points are fine.

The battery is reading 13 and a half volts, the fuses are fine, the ground points are fine. What else is there? I suspect the starter relay because the positive lead from the battery goes straight into it, so if it fails then the rest of the bike would have power issues right? But why would the kill switch rocking have anything to do with that? How would I be able to tell if the starter relay is dead?

Any other ideas?

Might be an idea to check the wiring leading to the starter solenoid, this can get very hot and burn out.