kawaskia fh721 revs to the sky

[backhoelover]

i have a kaw 721v in shop that acts as if there is not a gov on it. will idle perfect and it hits 3600 top no load and then all of a sudden revs like a indy car. all gov parts have been replaced and everthing is set to the service manual this thing has me shaking my head.
carb has been rebuilt
new lines
new fuel pump
new gaskets
throttle shafts are tight

any thoughts or if anyone has seen this will they send me a pm please.