That voltage you measure is the battery s no load reference voltage.
Motorcycle battery voltage at idle.
If lower than 12 4 consider getting a load test done.
If so this is good.
Specs for the reg rec show 14 3 14 8 is normal voltages also there are also 2 ref rec on this bike.
Lithium batteries spring to mind immediately as a battery that has a different usage and test scenario.
Battery is 12v agm only 1 month old.
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.
Both old alpine amp and new amp are rated at 14 4 input voltage.
It doesn t matter if the bike starts or not what you re looking for is a voltage reading.
During a normal ride a motorcycle provides about 13 14 or 15 amps while idling only provides less than 1 amp.
It s not a heat issue since new amp shuts down only when voltage increases.
If you ve got one refer to your battery manufacturer s recommendations batteries need both voltage and current but testing voltage is easy all you need is a multimeter also known as a dvom digital volt and ohm meter.
Your motorcycle s charging system check is complete.
Technically a motorcycle battery does charge while the motorcycle is idling though it does not provide as much amperage as when the motorcycle is at higher speeds.
You should see the voltage increase on your meter even further up to around to 14 4volts this will vary from bike to bike.
Now push the starter button and watch what the voltage drops to.
At idle battery is showing 14 2 3 and 14 8 9 when throttled.
It should be between 12 4 and 12 8 volts.