XS400 Problems first bike need advice and help PLEASE!

[neutrax]

i just bought a 1981 xs400 from a friend she said it ran and it did for a few test rides while i adjusted myself to riding it in the parking lot at my college ( i goto an automotive school so i was having fun with it) i decided to take it home and park it and it decided it wasnt going to start i jumped it using a friends truck. so i figured while it was running id get it home its only 3 miles or so. the bike made it 3/4 the way and died out right wouldnt start. we loaded it in the truck and got it home i took the battery in to charge it and make sure it was good its charged the bike turns over but wont start and now the lights both headlight tail lights and the dash lights wont come on the starter is rigged somehow to a switch mounted on the headlight but it crosses the solenoid to activate the starter any clue what might be wrong orwhere i should look i plan to take a dvom to the bike tomorrow and try to find a short but the engine isnt wanting to start and thats regardless of electrical problem ( i think it doesnt seem to fire) any help its greatly appreciated and i will use anything you can offer seeing as i dont know very much at all about motorcycle engines or otherwise thank you