I say free feed, but I have a 13 week old puppy that never stops eating...
we had to go to the ER vet because she ate so much she wound up with bloat which is life threatening!!!! She eats so well I worry about over feeding her. i had to ask the vet how much... how often. I don't think you will have this problem cause most yorkies seem to be picky eaters but just thought I would share what we went through cause it was a night mare!