GustineCA

I am hoping someone here can offer some advice. My neighbor just gave me a 1976 Yamaha DT 400 that has been sitting in the back of his house for 10 - 12 years. I checked for a spark and the motorcycle has none. Does anyone have any suggestions on how to go about finding why there is no spark? The battery is compleley shot. Does the motorcycle need a battery to start? My Honda doesn't? Any help is greatly appreciated. Robert