>>1840479*almost everything
there is a time to know when to part out a bike. That's still sustainable. But the problem with BSOs is practically none of the parts are of any value and if you start taking anything off them you've condemned the frame. Something nicer would maybe get rebuilt one day but a BSO will have to go to scrap metal because it's never worth doing a frame up build on a garbage frame.
The main line for viability of a BSO is whether the wheels and tires are good or not.
It's also worth remembering that BSOs aren't even assembled well. They don't work out of the box. They're rarely ridden much so in many ways they typically are actually in quite good condition, or atleast, there isn't that much wear on any of the parts, when they're 'broken'.
