With engine running, ensure system voltage is in the 13-14 volt range.
You need the test equipment and a bunch of knowhow.
A charging system test is done to check the internal voltage regulator. It can be done at any auto parts place.
with a regulator tester kohler sale one that will test most regulators
How_do_you_check_your_voltage_regurlator_on_your_motorcycle
with a kohler regulator tester
it is inside the alternater, not stand alone.
Usually the voltage supplied to your battery when the engine is running is about 13.5-14 volts max. If the output is higher or lower than 12 volts, then the regulator could be faulty. hope this helps
You will need to go to a repair shop and have them test the charging system.
have the battery checked and test the voltage regulator
Test/replace the voltage regulator. The year, make and model info would help.
To get to an internal voltage regulator first disconnect the battery ground ( negative cable ) then remove the alternator. Make sure you mark the cables on the alternator so you can put them back exactly where they are supposed to go. The voltage regulator is inside the alternator and you will have to take it apart. I'm not sure how the regulator is mounted in your alternator, it might have small studs with nuts on them, or small screws or bolts, or it may be soldered in. In the latter case you will have to cut out the voltage regulator and solder in the new one. If you are going to take out the alternator anyway you should probably take it to a parts store where they will test it for free and tell you if you need a whole new alternator or just the voltage regulator.
Check the battery voltage, bike not running. Start the bike (crank the rpm's up a little), voltage should be a couple of volts more than battery voltage. Check both voltage (running and not running) at battery terminals. Charge voltage isn't all though, if it doesn't stop charging when it should it will boil the battery dry. If you are having this symptom, it's for sure the regulator