Can you give us the following voltages, measured across the battery terminals:
- Bike off, having sat for a while
- Ignition on, lights on, not started
- Bike started, idle
- Bike started, 3000 RPM
- Bike started, 5000 RPM
If possible, unplug the R/R and perform the stator test. Just because you changed it doesn't mean it's good.
- Resistance (ohms) between each wire pair
- AC voltage between each wire pair at idle, 3000 and 5000 RPM
What was the reason for putting in a new regulator? These are not really known to fail. What regulator did you put in?
When you did put the stator in, did you inspect the rotor magnets? Even spacing all around?