Honda GOLDWING GL1800/A 2015 Owner's Manual page 215

Battery
Battery Charging
Refer to Safety Precautions on page 154.
Be sure to read the information that came with your battery charger and follow
the instructions on the battery. Improper charging may damage the battery.
We recommend using a charger designed specifically for your Honda, which
can be purchased from your dealer. These units can be left connected for long
periods without risking damage to the battery. However, do not intentionally
leave the charger connected longer than the time period recommended in the
charger's instructions.
Avoid using an automotive-type battery charger. An automotive charger can
overheat a motorcycle battery and cause permanent damage.
charger
212
Servicing Your Honda