Might be the original battery, but who knows? Either way it's junk.
You call Yuasa and they ship out a fresh one to you. Read the numbers off the battery is all you say. No need to home wreck what is oem right back in like plug and play. Good integrity and all that. You h-depot for those clips to mess up a perfect wire harness; is looking for trouble. Be smart or pay me later as the saying goes.
Yes, 6v times the filler caps. Each cell is 2v [x'3 caps] = 6v.
If you had 6 caps times 2 cells = 12v.
No, not an electric start bike with such a low amp battery.
Careful: The battery is a resistor against the light bulbs, meaning, you start the bike up without battery, it is watt ever the stator puts out. Meaning, if you have more volts feeding the battery by 2v, then boom goes a 6v bulb with over 8v's thrown at it. Might as well say the volt/reg sees zero volts, so it overcharges in other words > Blows everything!
Bulk vinegar at costco is your carb cleaner. It won't swell the rubber; cuts the varnish; needs hours if not the next day to see how she goes? Gunk brand 'carb clean' is how you finish off the rinse process of the jet and air passages.
You can even dip the head in [vinegar] and decarbon; Without taking a drill or brush to it. Just pull it out and let it dry for a few days; The carbon curls off.
Pull the exhaust pipe. Look inside the port. If the piston looks clean, no gall lines, she is good to go. You want to know why it sat? Sometimes a bike like this can seize and becomes a sitter. Before you spend a dime on it, you pull the pipe and see if she was ever seized? She might turn over, but the gall calls the move of the wallet.