scooter jerks at 50 miles an hour like its been held back .
by kevin routley
ride a vespa px 125 . its jetted up to correct jet and the carb has just been cleaned . but when riding the scooter at high speed it jerks and holds back ,but after a while it runs ok . does any body have any pointers as to what to do next . cards ok and the fuel line isnt blocked . any tips ?