If so this is good.
Motorcycle battery voltage when running.
Does your battery seem to be going bad.
This is a huge part of your charging system.
A low or failing battery can cause crazy readings during your testing.
Your motorcycle s charging system check is complete.
The alternator is fitted with a regulator that charges the battery while you ride.
If your battery is charging perfectly but your motorcycle still seems to keep killing the battery.
A healthy 12 volt motorcycle battery should maintain a range from 9 5 10 5 volts under the load for a good 30 seconds straight.
The relationship between your motorcycle battery and engine functions much in the same way as a car battery.
Be in the know on whether you actually need a new motorcycle battery or not.
With the battery fully charged and functional it s time to test for battery voltage drop.
This needs to be correctly charged and tested before you start and troubleshooting.
No need to go running to a dealership to spend money.
Replacing the rectifier which converts the alternating current ac from your motorcycle s stator alternator to direct current dc before recharging the battery is also recommended at this time.
What you are looking for is that all three of the numbers are similar.
Or you may find it s not the battery at all and a charging system problem instead.
Now switch your multimeter to read ac voltage.
While the starter is spinning observe the voltage.
It doesn t matter if the bike starts or not what you re looking for is a voltage reading.
Your battery may even be holding a charge but it s the cold cranking amps that may determine if your battery needs replacement.
Then measure the voltage from tab to tab just like before.
You should see the voltage increase on your meter even further up to around to 14 4volts this will vary from bike to bike.
A good battery should not drop below 9 6 volts over 10 seconds or so.
However it s important to note that normal riding may not be enough to fully charge the battery after being completely depleted.
Hook up your dvom in the same manner you did for the standing voltage test and have an assistant thumb the starter.
Now push the starter button and watch what the voltage drops to.
Your charging system is putting out the necessary voltage to the battery during a running condition past idle.
Replace the voltage regulator if the reading is higher or lower than the 13 5 to 14 5 volt range to prevent insufficient or excessive charging.
With the multimeter on the same settings as above.
With the ignition on and the bike not running switch on the lights and you should see the voltage drop slowly as the lights use up the power in the battery.
Video is your harley davidson or other brand motorcycle seem to be cranking over slowly when starting.
Perform a current draw test.
