2007-2009 Kawasaki KFX50 service manual, Page 94Get this manual
5FUEL SYSTEM Remove the needle clip and jet needleCheck the throttle valve and jet needle for wear or damageNeedle Clip Throttle Valve
Jet Needle Groove ASSEMBLY Reverse the "DISASSEMBLY" proceduresInstall the throttle valve into the carburetor bodyAlign the groove in the throttle valve with the throttle stop screw on the carburetor body