Originally Posted by 2door
If the bike was running good then started with this "bogging" thing I doubt you're looking at a jet size problem. Something else is responsible. You say the same thing happened with the CNS carburetor and now the NT. They both ran good then started acting up.
If it was jet size the problem wouldn't just appear after a few miles.
I concur with fatdaddy in that you might have a float or float valve problem that is allowing too much fuel in the bowl. Are you using an in-line fuel filter? Possibly the float valve is not closing due to trash in the seat.
Are you using fresh gasoline? 2 cycle mix has a short 'shelf life' and should only be stored for a few weeks. Old mix won't perform as well as a fresh batch.
What plug gap are you running. .024 to .028 is a good ball park place to start.
Also keep in mind that the needle clip position only effects fuel flow at or below 3/4 throttle. Above that, up to WOT the main jet determines fuel/air mix.
Great response, thank you. I have checked the carb and cleaned it out, as well as using fresh gas. Spark plug gap is .026. I am using an inline fuel filter too. I called a guy who repairs these bikes and said something about it being piston rings? I'm good with the basics but I'm not very knowledgable about the actual engine. He said the piston rings probably need replacement. Literally everything on my bike is 100% good to go, working, and clean, EXCEPT the engine. I have not looked into that because I don't know what to do or how to work on them. The engine is VERY oily inside and out. I repeat: I am using a 40:1 ratio.