I once sprayed my cable with a lubricant and then 1 week passed before I got to ride it. When I went to start it the throttle was seized.
What had happened was the spray lube dissolved and diluted all the crud that built up inside the cable over the years, then this runny shit took a gravity ride down the cable into the carb body, drying in the weeks time and seizing the slide.
A healthy dose of carb cleaner fixed it.
Try what Larry and kyle suggested first, then if it's still sticky, take the 2 screws off the top of the carb and remove the slide and choke.
Twist the grip and see if the slide moves freely, if it does, your cable and grip are ok, if not , it's in the carb and slide assembly.
A healthy dose of carb cleaner will fix it.
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