While I admit you make a good point, in that we don't know if he built it, if it wasn't him it was likely a brother or friend he knew. In which case, that would be the fellow I'm admiring.
It seems less likely somehow (though not impossible) that the fellow in spandex in that picture built the road bike he rode in on. He has money, therefore he likely bought a bike. This kid's message amounts to "I may not have much, but I have a bike too. And if anything happens to it, I have the means to have another one." When you can get raw materials and have the knowledge to bend them to your will, that is a heck of a lot of power. And to a kid, a bike is a treasure, a way to go so much further than you can walk in that time, a sign of status, often their most important possession.
I remember that's how it was with me.
