Dirt bike tire size questions?

Well, I picked up a Kawasaki Dirt Bike that I have been restoring, its a 1975. It still has the original (and now bald) rear tire on it. The tire either says the size is 3.00-14 or 300-14. I believe its metric measurements but not sure. I found a nice tire but it is size 300-16... I was wondering what the differences between the -14 and -16 are at the end of the size code. Will a 300-16 tire replace my 300-14 tire? Thanks