Trouble starting - starter motor tries to turn the engine over, but can't quite manage to do do. I cleaned connections to and from solenoid and to starter - didn't affect things.
Screws at battery connections a tiny bit lose - tightened maybe a small quarter turn.
Battery voltage before trying 12.4/12.6. Voltage while trying 10.something to maybe 11
Jumping with a car battery it fires right up.
Then: Idle 13, rising to 13.8/14 at just under 4.000 revs
Now on a charger.
Battery = toast?
I can't tell from your info. The way to know for sure is fully charge and load test or one of these type testers https://auteldiagnostictools.com/products/bt506?utm_source=bing&utm_medium=cpc&utm_campaign=Autel%20Diagnostic%20Tools&utm_term=2323130631271801&utm_content=Ad%20group%20%231
If I was a betting man I would go with your diagnosis though. Oh, Is your battery lead acid or lithium whatever?
Lead acid. No lithium in my bike, yet.