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

[oldkid]

Not sure Phil. I have a 150cc that I don't ride much anymore, but when I did and also
when it was nearly new, it had a miss and would not get up long hills good. I changed the plug to the iridium plug, replaced the CDI with a new High Performance model, but what helped the most was I removed the old vacuum fuel pump and replaced with a new electric low pressure pump with fuel pressure regulator. Also upgraded the fuel filter. Now itwill indicate near 60 mph on the speed. Don't know for sure, but I guess all the changes helped some, but together sure fixed the problem.
Tom

[airboatphil]

thanks for the reply oldkid !

[airboatphil]

I put my timing light over the plug wire and observed the light pattern from idle to accelaration until the miss occurs..... It is definatly in the spark going to the spark plug.... I still say I am " hitten' the rev limiter in the CDI " . I have put a new CDI but not the performance model. There is a chance that I got a bad CDI out the box but I'm still puzzled ?

thanks,
phil