A coil-over throttle return spring device mounts onto the exterior of the carburetor and allows the user to adjust the throttle tension without having to remove the device from the carburetor. The throttle tension is adjusted by moving the ring along the length of the body to lengthen or shorten the spring. A coil-over throttle return spring device kit comprises the device and a bracket and hardware used to easily mount onto various size carburetors. The bracket and hardware allows for adjustability depending on the size of the engine and length of cables. A method of installing a coil-over throttle return spring device kit onto a carburetor and a method of adjusting the throttle tension.

A throttle valve device ideal for small, inexpensive implements is provided. The throttle valve device having a damping member for slowly closing a throttle valve. The throttle valve device (1) has a throttle valve (4) that is fixed to a throttle shaft (5) pivotably supported in an air intake passage (2) and that is urged towards the closed direction, the throttle valve (4) adapted for adjusting the amount of air passing through the air intake passage (2). A through-bore (31) penetrating a shaft bore of the throttle shaft (5) is formed in a body, and a damping member (8) having frictional capabilities is inserted into and supported in the through-bore (31) in a state of pressing against the throttle shaft (5) inserted through the shaft bore (51).