Did you ever bypass kickstand safety? Or at least zip tie the switch to the shut position?
I just had ANOTHER one that the kickstand safety was the issue. Last week as a matter of fact.
The guy thought he was going to have to buy a fuel pump and some other stuff. He was so happy when I fixed his bike for free.
Question..... If you ride it like you stole it does it still pull hard all the way to redline? In all gears?
If it's still a beast and and pulls hard to redline in all the lower gears then the fuel pump is fine.
If it bogs when you beat it in the lower gears then you could have a fuel pump issue.
If that is the case I recommend getting a low mile used gen2 assembly. Yes the plug is different but it's easily
spliced.