1979 Yamaha XS 650 Diagnostic question.?

So I have an old 1979 XS 650 and it has been sitting for years. I threw a new bat. in it and everything seems to be lighting up. I'm hitting the electric start and it is working but there seems to be no spark. I am trying to figure out what is going on here. Can somebody help? is this the coils, people say they are a little crapy.