Battery not charging while running - 2000 Harley Davidson FXDX Dyna Super Glide Sport

Test the alternator. The battery light is for the charging system. Once the charging system is working with the engine running, the light should go off. If your light stays on with engine running, the alternator may need service or replacement.

To test the charging system, just put a voltmeter on the battery with engine running. The voltmeter should register at least 13.5 volts- alternator is charging. If you only show battery voltage with engine running, like 12.2-12.8 volts, the alternator or charging system is not working. The battery light should be on to signify this.

When a battery dies while the engine is running it is not being charged. When the charger is working the engine will run without a battery

I think you mean a 69 CB350. It sounds like you have a bad battery since the battery charger won't charge it.

On this bike there is an alternator and rectifier that combine to charge the battery whenever the engine runs. If the battery won't hold a charge, the charging system wont work.

Replace the battery.

Will the battery stay charged with one terminal disconnected?
if yes the you have a wiring problem. If no get a new battery.

What is the battery voltage when mover is running?
12.6v = not charging while running
13.7v = good charging

a lawn mower battery is only good for a couple years when keeping it charged and testing voltage doesn't tell you what is has for amps is the volt meter read more than the off voltage while running then it works they only have a 4-7 amp charging system

How old is your battery?
Is your battery being charged when the engine is running?
Have access to a 12 volt dc voltmeter?
Put across pos. and neg. side of battery while engine is running should read ABOVE 12 volts dc?
then check voltage when engine is off and compare?
if you have a higher reading when the engines is running than when engine is off then your charging system is charging, Then battery is suspect.
if it is not charging or no difference in voltage when engine is running or isnt running then look into the engines charging system IE: charging diode,good and clean ground wire connections, etc: without knowing more detail this is a basic check.
Note :Run your engine at higher than idle when doing these checks

Try unhooking the battery while it is running,if it dies,then the charging system is defective,if it stays running,the connections on the battery or the battery itself is defective

Sounds like you need to replace the Alternator

Check the big battery cable on the starter and make sure its not touching metal anywhere. Did you get sparks at any point during your job. Check the fuse links...pull on them make sure they are intact

Even if the battery is new, if it is not charged properly it can run down pretty fast. To reset the battery I recommend running the battery all the way down - charging the battery all the way back up to full - and then repeat. Also, make sure you do not charge the battery after it is full. Most phones or charge units have signals to tell you when the battery is fully charged. Do not charge the battery overnight.
These are the best ways to protect the life of a battery.