Ha! I can relate. Not as dramatic experience that I had.
I had a 76 DT 125 for plonking around the dirt/fire roads around our cottage. It had a chronic rusty cam on the flywheel. Which means the rubbing block on the points would work great for a couple hours and then slowly cause an ignition misfire and eventually lead to a DOA engine. I got quite good fixing it trailside with the toolkits crushed Yugo Phillips screwdriver and rock to shock the flywheel off (no joke).
One day me and my buddy with a POS of shit RM125 are blasting around the gravel pit on our bikes. Like you, hot as f@$k. My bike starts to misfire. By this point, I'd had it with this stupid thing. I stop in the middle of the pit, Ger rides over, "Whats the matter?" I explain "I'm gonna pin the bitch until it seizes or detonates, either way, this isn't leaving the gravel pit". I think Ger thought I was just joking because I was pissed.
With that I proceeded to pin it and do a 50 foot flat track style donuts around him. The air was thick with the dust I kicked up, I didn't really know where the feck he was, and he didn't move for the same reason. The whole time, the bike won't rev any higher and is screaming WAHHHHH-<FART><BANG>-WAHHH. Everytime it <FART><BANGED> it would try to get me off its back by high-siding.
It never did seize or detonate. But it never ran right after that day. No amount of point adjusting would bring it back to anything near normal 'power'. Some poor asshole stole it from our cottage. I hope it finally died, deep in the bush with the thief on its back.