The carburetor throttle slide spring is a critical mechanical component of aftermarket carburetors used on GY6 125cc to 150cc engines, such as those found on the Honda Ruckus GY6. It is installed inside the carburetor and ensures the return of the slide to its closed position when the throttle is released.
Its function is to:
provide the necessary return tension for the throttle slide
maintain a stable idle
ensure immediate engine response
prevent the slide from remaining partially open (unwanted acceleration)
optimize the progressive opening of the throttle according to the rider's intent
A spring that is too weak or worn can lead to the slide not returning properly, creating a "rich" engine with imprecise throttle control. A spring that is too stiff can make the throttle feel harsh, jerky, or difficult to manage at low RPMs.
