First nothing was assumed (you know what they say about something being assumed right?) I was going off exactly what you stated, though I did state pop rivets mistakenly instead of rivet nuts, but either way I was going off exactly what you stated for their shear strength of 340lbs.
I also said nothing about hitting an object at any speed. I said any kart whipping around at decent velocity or g forces. Again you're assuming there as to what I said, when that's not what I said.
The whole of what I said had to do with the shear strength of the pop nut vs the shear strength of a standard grade 5 bolt. I also went on to state that if it were me I would not trust it, but by all means do what you will, just make sure to wear a helmet at least lol.
I'm not bashing you, do what you want, I personally just would not trust it. I remember helping my dad as an older kid restore a side car for a motorcycle. Well he was putting new sheet metal into the bottom, drove a rivet about every 6 inches along the edge of the sheet metal, plenty to bite into on both the sheet and frame. He goes to get in, puts his foot in, and goes to step/slide in to sit down in it just because... and that new sheet metal floor was destroyed. Rivets popping out, breaking off, etc. Heard a lot of words I never knew that day lol.
I'm just saying that I personally won't trust simple rivets where a bolt would work just as easily. I'll take the 3 to 4+×'s strength upgrade on that 340lbs any day myself.
