Motorcycle Carburetor Idle Adjuster Screw kit For 21-34MM Carburetor Idle Speed Screw This idle adjuster screw kit is designed for use with 21mm to 34mm carburetors.It allows precise adjustment of the engine's idle speed by controlling the throttle valve.The kit includes a threaded adjuster screw and spring, compatible with standard carburetor models that support external idle speed tuning.The screw fits into the carburetor body and interfaces with the throttle slide to set minimum RPM.Installation is straightforward, requiring no modifications.This part is intended for replacement or repair of worn or missing idle screws on compatible carburetors.