Ive found for the most part a small number of forums get 85%+ of the forum traffic as they are established forums. Potential forum users would much rather participate on an established forum that to join in on your new one.
Asking friends to post doesnt work either – they usually post once or twice and then vanish. 
I think I am going to give it another shot within the next month or so and if it doesnt get a bit busier Im just going to ditch the idea. Currently the forum gets “view” traffic, but no one is posting.
So hey join my forum and become a poster and I will hook you up with some nice links, or join your forum and post as well 