I wouldn’t mess with a di or a rfi even it were free I had a rfi once I hated that thing great when it ran good but the key word there when. I would look into getting a different ski than mess with that thing
clean your raves my bet would be something other than carbs because if it was running out of fuel it would surge. Which I believe it’s not from what you’re saying. Sounds like you got a sweet setup there get it right she won’t do you wrong