My friend has a 1997 sportster 1200 but the battery will not hold charge. She replaced the battery and still wont hold charge. So if anyone has had this problem or might know what this problem could be your ideas would be appreciated.

 

I guess I'd put an amp meter in line with the battery and first see if the alternator is charging the batter when running, and second to see if something's bleeding off the charge when it's not running.

 

like ronn39 said. You'll have to figure wether the bike isn't charging while running, or leaking current while bike is off. Easiest thing to do is start off with a charged battery, so use a charger first, or barow another battery you know has a full charge on it, and use a voltmeter with the bike running and measure voltage between positive and negative terminals, while running you should be about 14 volts or so, if it read 12 volts or lower, then theres something wrong with the charging system. If you are getting around 14 volts while running, then the problem must be drainage while the bike is off. Solutions: If charging system is at fault, get yourself a manual, it'll give you all the troubleshooting steps to test the entire electrical system. If its drainage while the bike is off.........it can be even more messy, most likelly something is grounding somewhere allowing for a complete circuit, best way to go is follow your positive battery terminal through all the components it is directly connected to first, like ignition switch's, solenoids whatever. And once again a manual can help with testing various components. Also while your at it, clean up as many of the electrical terminals as you can. Good luck.