Factory manual specs 14.1-14.9v no load voltage for regulator, & 12.8v for battery (no load).& a 0.2-2.5v rise from this when charging.
Your Supposed to check charging circuit @ 5000rpm. This can be quite disconcerting for anyone even slightly mechanically sympathetic.(seen it done in bike shop
)
Quick & dirty~I've allways blipped the throttle with the lights on & watched for the flicker as the reg. kicks in & out.
FWIW, i suspect your regs not "dying" a long lingering death
, its most likely either DEAD or ALIVE.
May be as well to check your alternator windings & all the other wiring connections associated with the charging circuit as that burnt pin's telling you something.
Hope that helps, not sure it does.