At idle battery is showing 14 2 3 and 14 8 9 when throttled.
Motorcycle battery voltage at idle.
If so this is good.
Both old alpine amp and new amp are rated at 14 4 input voltage.
Your charging system is putting out the necessary voltage to the battery during a running condition past idle.
Battery is 12v agm only 1 month old.
During a normal ride a motorcycle provides about 13 14 or 15 amps while idling only provides less than 1 amp.
It doesn t matter if the bike starts or not what you re looking for is a voltage reading.
Lithium batteries spring to mind immediately as a battery that has a different usage and test scenario.
If lower than 12 4 consider getting a load test done.
If it keeps creeping down the longer it sits order a new battery or look for a parasitic drain in the bike.
Now push the starter button and watch what the voltage drops to.
It s not a heat issue since new amp shuts down only when voltage increases.
Measure the battery voltage.
That voltage you measure is the battery s no load reference voltage.
Specs for the reg rec show 14 3 14 8 is normal voltages also there are also 2 ref rec on this bike.
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.
It should be between 12 4 and 12 8 volts.
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.