Hi and welcome to Yorkie Talk Randyrambo and Rambo. The only thing I can tell you is that my friends who have male dogs even though they were neautered still continued their "humping" activities. It's a dominence (sp) thing with both female and male dogs even when fixed, not so much sexual.
Try to post pictures to the forum of your little guy., all of us here love to see little Yorkie pics.
Sorry i wasn't much help, I have only females but this is what I have seen
and heard.
