...cool on the carb thing...
..i had CK50QT-5 on my original carb...
..i've been able to determine those numbers mean it's a slightly different build than some other A50s...
..translated from a cpl different chinese scoot sites i get the following...
.. "the engine is imported from Taiwan, Hsing new piston, piston ring, with the Taiwan imported carburetor, reducing friction, combustion, lower fuel consumption, "
..the boldface kinda explains why my scoot requires larger main jet sizes...i think....