Another charging system problem

[eclynn1]

I have'nt been around for a while, but my grandsons bike has a charging problem and I'm not sure
where to start. The battery is dead and will not take a charge. The previous went through similar
problems. Would'nt hold a charge so we figured it was the battery and replaced it. Now the new
battery is doing the same thing. I think the battery has been cooked, I checked the water in it
today and it was almost completely dry.
The bike is a 2000 model GZ-250 with about 6000 miles on it. I've checked all the fuses I can find
and all checked good. How do I check the leads from the stator and the rectifier or voltage regulator? I have a VOM and test light, but not sure what reading I should be getting on the VOM.
Also, I'm assuming the bike should be running to check the stator output.
Any help will be deeply appreciated.