It is easy to remove the battery from your Vee. Take it out and take it to an Auto Zone or parts retailer that can load test the battery. Won't cost you anything and that is really the only way to test a battery.
Your voltage readings seem high. That could be your meter not calibrated.......or it can mean the battery is a cause. 12.5 volts is suspect, borderline at best. The high voltage readings at higher rpm can come from the R/R trying to force charge into the battery. A sulphated battery doesn't like to take charge and the lower voltage readings from it are telling the R/R that it needs to charge at a high rate to build up the battery. The battery will take a surface charge but its ability to store larger amounts of current are gone. You have already had it fail to start, I'll bet money it doesn't pass the load test.
12 DL 650 Wee II-04 1150 RT-03 DL 1000 "VEE"-04 DL 650 "WEE"
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