I beg your patience with the newbie questions, but would appreciate some help. I'll give as detailed an explanation as I can.
I just bought a 75 CB550, and after running it fine for about a week, going on little local neighborhood rides (still on the temporary permit...), the battery died out on me when I performed a battery test (measuring output with high beams on while engine not running, per the manual). So I brough the battery to a local auto garage, where they used a trickle charger to recharge it. Slapped the battery back in the bike, hit start, and the starter was working fine. Engine fired a couple of times and I let go the starter button, but it didn't catch. When I hit the starter button again, dead: no electrical on the bike whatsoever, no lights, no nothing. I thought I might have heard a slight click from around the left side cover, but not sure.
The battery was turning the starter fine right up to the second the bike went dead, so I am discounting it as the culprit. I've tried turning the key, giving it a jiggle. I also swapped the main fuse with the backup (although potentially the backup is no good). Any suggestions?