Sounds to me like an electrical issue. Would definitely recommend unhooking the PC and seeing what happens. Also, do you still have your GoPro? Maybe mount it to your tank and watch your dash and record what happens so we can see an example of whats happening?The bike runs like a fine clock 99% of the time. On throttle, off throttle, up and down the range, revving in neutral... the bike acts like it always has.
The only stumbling/stalling I've had is immediately after it cuts power in the upper rev range.
Just curious have you tried to pull the fault codes from the dash? Just because the check engine light is not on doesn't mean there aren't stored faults. I have been a mechanic for going on 13 years and running fine at low rpm and losing power in high rpms kinda sounds like it may be starving for fuel. If it had low battery voltage to the injection system i doubt the fuel pump would even come on and if it did it should definitely set a fault.Haven't had any time but will be checking the fuse box, my battery's readout and speed sensor wire tomorrow. Thanks for sticking with me through this fellas, it's driving me crazy!