First, make sure the battery is good. Check it with a volt meter, with engine off you must have a little more than 12 volts. With engine running at idle you will have around 13 volts, and at say 2000 rpm you should have anywhere from 13.8 to 14.5 volts. If when the engine is running and all is good, then replace the battery, if the charge is still at only 12 volts when the engine is running, then it would be the stator. That's the charging system. Now, just depends what make of bike.
You might have a bad battery they arent very expensive
thats an easy one. i had the same problem with my gs500e. its the violtage regultor. definatly
yes
Put a battery charger on it.
Yes. Cold weather can deplete the charge in any motorcycle, marine, or automotive battery.
No, It will charge ok while connected in the motorcycle.
A battery that won't hold a charge has a dead cell and must be replaced. This is assuming there is not something on that is pulling power from the battery.
Any 12 V battery charger will charge a motorcycle battery. But it is best to get one with low amperage such as a 4 to 6 amp battery charger. You can use a trickle charger to keep the battery charged on my motorcycle during storage.
Well i would suggest connecting the battery...
Depends on the condition of the battery. Most will hold a charge for at least 6 months if they are not connected to anything.
Motorcycle batteries may be 6 volt rather than 12 (check this) and if they are 6 volts, switch your battery charger to 6 volts or you may damage the battery.
Very gently. A motorcycle battery can't take as much charging current as a car battery, so you need to use the lowest setting on your charger.