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, proposed preliminary checks (if have not been tried) would be with the fusible links from either the battery's + terminal or 1 terminal of the starter solenoid.
Still 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).
All other tests would require a volt/multi-meter.