Had an odd problem today.. Rode out to meet up with some guys to go down some Greenlanes. Bike started on the button as usual, no issues.
Met up with the others and one for the guys had broken down, couldn't fix it so awaited recovery. We were going to carry on.... Turn the ignition on, and nothing happened. No lights, so dash, no starter. Nada....
Bumped the bike and it started straight up. But the indicators were struggling when turned on and the dash flickered at idle. Guessing it was totally running off the engine power.
As soon as I turned it off, again no power and would need bumping again.
Went down a few lanes and called it a day. Took the battery out when home and checked the voltage. Was at 12.5v... So nothing suspect there?
Have you got a multimeter you can put across the battery terminals whilst running to see if it's charging?
Could be a faulty stator.
I keep a Sparkbright monitor on the bench to check for problems - just put the leads across the battery terminals whilst running and, if it shows a green light, then all is good