I'm having issues with my ride topping out around 26mph/4krpm. I've been doing a lot of research online and I believe it should be topping out around 40 mph? I've pulled and fully cleaned the carb which wasn't that dirty. Changed plug (shows signs of running rich) dark and wet with gas. Checked spark with inline spark tester which is great until about 4k rpms and flickers with the sputtering. Air filter is good. Muffler is good. Sounds, runs and drives great up until +/- 26mph/4k rpms. Then spits and sputters. Any advice would be highly appreciated.
Thanks,
Joe