Sorry for any misunderstanding....
I'll put it another way.
I one were to run one of these admittedly old-tech engines downhill long enough and fast enough, running at redline or above without a perfect mixture, it would encounter some form of
catastrophic failure. Otherwise know here in north east Ahia as a "meltdown". (although not the type experienced by many folks in Holly-weird)
Could be in the form of a snapped rod, bearing failure, ring or piston skirt breakage, seizure, ect. In other words, you turn your engine into a small pile of inexpensive scrap/tears/swearing/capital loss.
If one were to run one that hard, they should not be surprised or upset when the whole thing goes "kablooie"
(tech term there).
I didn't mean the engine would literally "melt down" that would take a lean run of about 30 seconds at which point the aluminum would turn to clay (once again not literaly) and melt....I've seen it in many two stroke engines.