Is this a piece of early italian tunining?

[carlos fandango]

Or just a bodge
Just managed to free a siezed barrel of my new project a s1 li150, and found this

It sees to have bee filed all the way round th top of the piston, rings as well

[twin]

i think its a bodge,

[Andy Pickering]

Ive seen windows in pistons before..someone used to do this cant remember who though..maybe wildcat in the 80s someone like that?

[joespeed]

thats a standard piston ,could be that someone has rubbed it with a wire brush.or file or just emery paper,
regards
joe

[carlos fandango]

Its not the windows, its the filing/ grinding at the top of the piston ! i just can`t understand why they would do it. the only raeson i could think of was if the piston was a replacement oversize and they tried to file it to make it fit, and had to ram it in