I am wondering: can it be so, that this block is bored for something 2mm bigger, (950)and then have had special made sleeves to fit larger holes in order to lower displ. again? Though, why would anyone want to lower it ?
There is no text or marks on the sleeves. As mentioned, the block itself says "R900", and the pistons are stamped "haindst", which i understand is Henry Ape industries.