Dong Fang 150TKB Reverse Trike problem ?

[airboatphil]

Year model is 2013 with a 157QMJ engine...... 750 miles on the unit....the bike seems like it "hits the rev limiter" past 20 mph ? the carb has been replaced with a genuine Keihin...the original carb was one of those copy's.....so I decided to order a new CDI...still the same thing ? I went through all the grounds,etc ! This thing has me puzzled cause I am a good mechanic ! It starts fine and the auto choke works as expected....the acceleration is good until the speedo get to 20 mph then it has a bad miss..I know it's got to be in the ignition !Please help with the worst case thing you have came across ?

Thanks,
Phil