Piston identification on Z1

Do these look like OEM pistons for a 73' z1? I scraped off some carbon on one of them and there is a circle in the middle and a small arrow. No numbers that I can see

from what i can see they do,measure the bore

They are 66mm, but I thought the weisco pistons you could drop in were also 66mm, this bike was thought to have a piston kit in it.

Those are cast pistons, no doubt oem. Wiseco never made a 66 mm piston for the Z1

Too bad.. I thought I was going to be able to get rings cheap! Appreciate the help, I got another dilemma you all might be able to help me with. The guy who sold it to my old man 30 years ago said it had a piston kit in it, he also said it was a 73 z1 motor. The engine # is
z1e 075018.

The engine is painted black like it is a 73, the title says its a 74, and according to zedder its a 75. Any clue?

zedder.com/Info/75%20Z1-B%20900.htm

KLD wrote:

Too bad.. I thought I was going to be able to get rings cheap! Appreciate the help, I got another dilemma you all might be able to help me with. The guy who sold it to my old man 30 years ago said it had a piston kit in it, he also said it was a 73 z1 motor. The engine # is
z1e 075018.

The engine is painted black like it is a 73, the title says its a 74, and according to zedder its a 75. Any clue?

zedder.com/Info/75%20Z1-B%20900.htm

The numbers don't lie...it is a 1975 Z1-B...at least the cases are...

Does the top of the block have an o'ring around the cam chain slot?

Yep.. wiener shaped

73s didn't