Motorcycle Questions? Ask a Mechanic.
Hi and welcome to JustAnswer,Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially and if have not been tried; inspect the battery & ground lines and/or check/clean the battery cables + terminals as a preliminary consideration. Better yet, have the battery externally charged and then LOAD TESTed (even if new and just for the purpose of eliminating it as a suspect).
Still, proposed secondary checks (again if have not been tried) with the use of a multi-meter on:
Please post back results / observations of the above once tested.