Does this machine have a cable from the carb to the handlebar?
If so, diconnect it at the carb and try to work it manually, that will either comfirm the cable is the problem or the choke rod at the carb is gummed up from the crappy fuel we get at the pumps now adays.
If it is the cable try squirting some penetrating spray into either end and let it soak in and repeat for a few days while working it some.
If it is the choke rod, try spraying it as well, but disassembly of the carb maybe in the near future.
FDXX75
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