150cc gen 5 maddog wot issues
 

Ok I know I'm not a complete dumb ass I been worken on mopeds for 9 yrs now granted all 50cc, had one bored out to an 80 for 5 yrs never had issues. Bit anyways long story short my bike use to hit 57, bogged once at wot so I changed carb adjusted valves changed fuel pump since most stock parts suck. Have literally done everything even tryed disconnecting auto accelerator. What it's doing thow is I can hit 50 for about a good 3 miles straight an then slowly loses power till its at 45 then runs fine I can rode like that for a few feet then wot at 50 for about another mile an back to slowly dien down. The bike has 10000 miles on it. Spark is amazing im just at a total loss an dont know if im missen anything. I have even checked all vacuum lines. No leaks. I'm hopen someone here can help me.

My first guess would be a fuel delivery issue but who knows?

Too many changes at once. I would put the old fuel pump back and check that the vacuum line that powers it isn't cracked or kinked.

What size jets are you using? Did you tune the carb?