If you want to do an OnD dirty load test (sometimes called a drop test):
a) Charge your battery.
b) Select the 0-20vdc scale on your VOM.
c) Turn the ignition switch on with high beam selected, operate the starter and watch the VOM. The voltage will drop, but should not go below 9.5vdc. If it does, the battery is at end of its service life.
And this is the quick and dirty OnD open circuit voltage test:
a)Turn on high beams for ten seconds, turn it off and wait two minutes.
b) Disconnect the negative battery terminal.
c) Take a voltage reading with your VOM. You should get a reading of 13vdc or a bit over.
note: a normal battery will read 12vdc until almost exhausted. A good battery gives the one volt that keeps everything working.)
d) If <13vdc, try recharging and repeat test.
e) If no joy, replace battery.
While I'm at it, I may as well include how I do a charging voltage test:
a) VOM set to 0-20vdc, connected to battery.
b) Start engine and rev it up to about 3K and quickly read the VOM. It should be between 13.5vdc and 15.0vdc. If you have daytime running lights, it will be on the low side but should not be below 13.5. Last time I checked mine, it was 14.6vdc.
Note:
If it is over 15vdc, the reg/rec is probably bad and you have been blowing headlights.
If voltage does not reach min, yet rises above 12vdc, it could mean:
- battery cannot hold a charge.
- something in the electrical system draws more current than the alt can supply.
- charging sys fault.
If the voltage does not rise above the batt voltage, it could mean:
- Charge sys fault caused by broken or disconnected wiring between the alt and reg/rec, or batt.
- Fauly reg/rec or batt.
- Loose/corroded batt terminal screws.
- Batt at or near end of service life.
Unless you are into pain, and enjoy the pungent aroma of burning flesh, remove rings and watches before working on a DC system. Belly button piercings are ok as long as you keep your shirt on.
And, as usual, any smoke emanating from your bike as a result of trusting my suggestions is not my fault.
