New to the VTX

I have a 2003 VTX 1300S, it has about 3800 miles on it, kurykian hypercharger, and DG Hard Krome pipes. I'm having an issue with rev out under load. Many have said it's a backpressure issue, many have said it's a jetting issue. I'm beyond confused since my last cruiser was fuel injected. I ordered baffles (would have anyway), but wanted to get opinions here. And does anyone know the stick jet sizes?