please explain the theory here

Looks like someone tried to do something with a rotary grinder, like on a drill or a dremel, and lost it big time.

WOW is that the new hot ticket! did the bike run like that?

That's an old tuning trick, try and create "swirl" in the cylinder, with the 4 points in the pattern. Royally fucked up that one on the top of the pic, though. Ouch.

Yeah but the swirl only works if it swirles counterclickwise becuz of the northern hemisphere;

True enough, so I'm guessing in Oz, the pattern would be reversed.

This is the attempt to create a swirl effect gone horribly wrong. It's difficult to do in 2 strokes.

On 4 strokes it's much easier. Take the valves and use a machinging center to put a light dimple pattern on the combustion side face of the valves. The velocity of the fuel mixture and pressure from the combustion cases the mixture to flow across the dimples (air pressure differences) which "swirls"

The goal is more efficient fuel mixture burn and also a more complete evacuation of exhaust

Looks to me like all this did was lower the compression ratio.

Paw Paw