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Hi all,
Really stuck could someone tell me what this part is called?
When I took the carbie off the mower I ended up with this in my hands.
Would like to know what it does and if I can't get it back on can I lock tight what's left?
Thanks in advance

Discovered.
It a pilot screw (16016-ZG0-W00) and if anyone is interested here is a write up on it
https://www.howtomotorcyclerepair.com/how-to-size-your-pilot-jet-pilot-screw-explained/
Happy days