Piston Numbers

Hi guys,

Could anyone shed some light as to what all these numbers on top of the piston mean?

Piston

Piston%202

My particular piston has:
18-15
28959
53-93

Cheers

In this case you have what looks to be a TM KZ piston.
53.94 is the piston size in millimetres (diameter)
This is the exact size. KZ engine pistons, unlike some other engine types, are stamped with their exact size rather than under or over sized, like an Iame KA100 for example.
A 48.2 KA100 piston is actually around 48.1mm in diameter.

The others I don’t know, but would assume to be batch numbers of some sort.

Not a number, but the arrow/triangle mark indicates which side of the piston points to the exhaust port.

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