You got it
@Triton Thrasher . It's the tip of a plastic chopstick that I had used for years as a rough TDC gauge - good enough for tappet adjustment, etc.
About a year ago it must have got caught in a valve pocket on the Commando and broke the tip (55mm) off.
It's big and hard enough to hold a valve open so had to come out.
If I couldn't retrieve it through the spark plug hole the head would have to come off.
Moved that piston up close and poked with a piece of wire and torch until it was just under the hole.
Got a length of thick braid fishing line, about 120lb, made a ball-knot in the end and lightly taped it to the piece of wire.
Then dabbed a bit of super-glue on the ball knot and poked it down the hole onto one end of the chopstick piece.
Waited for a minute then pulled the piece out.
I only use paper drinking straws as a TDC tool now!
So... whatever you're using as that tool - make sure it's not breakable!!
Cheers