I can only tell you what my experience was. Accessories consist of a tach, an electric temp gauge, three light bulbs one each for the tach, the temp gauge and an oil gauge, electric chokes for the carbs, and a retro sound radio, no amps. There are no other added electrical draws, no AC, no electric windows, seats, nothing. Before the Halogen swap, no problems with the low amp alternator keeping up--over 30 years --same style charging system and the alternator had been rebuilt within the year by a professional rebuilder and a new battery installed. After the conversion, drained the battery fairly quickly when the lights were on. Two to three of hours cruising around and then would hardly start. Swapped over to the 100 amp alternator (probably a little over kill) and that solved the charging issue. So I cant say about anyone else's experience with an H4 Halogen conversion except to say that my low powered early 60s style alternator would not keep up but that an upgraded 100 amp does keep the battery from discharging when the lights are on.
