I don't know if it helps you too entirely much but I watch mine out of curiosity all the time. Mine goes to 20:1 when there is no load and I am coasting in gear. I have no issues however, if I tap the throttle even the slightest, it drops back to normal.
Thanks! When mine isn't freaking out and losing power, that's also true for me.
Good to hear the behavior is part of a general pattern.