I have an 05 KFX 400 with a very strange problem. The bike will start perfectly and, in neutral, it will run and rev great but when riding it, if I go to give it full throttle in any gear above first gear, cuts in and out. I'm pretty sure it's an electrical issue because it doesn't "bog" down. It's pretty instantaneous.
I have replaced the CDI with a Pro Comp box, replaced the Gear Position Sensor, replaced the spark plug and nothing has helped.

I'm at a loss. Any help is greatly appreciated!!

Thanks.