If the engine is not running as it should, hesitant throttle pickup or poor starting, have you thought about a complete carburettor overhaul?
The part shown in the image, is just one item of a few you may require to return to smooth running and first prod starting.
Other items you may wish to consider:
Add as many items as you wish to the same shopping cart, a new cover 140251903 diaphragm 430280016P clip 16044007 & screw 920091365 for example, and still only pay the same single fixed price shipping cost.
This component may have other applications within the Kawasaki model range.