<human>: So this TIFU just happened and I'm furious

I was on a biking trail near my house. This area has dirt jumps & steep trails. I had just gotten a new Norco One25 and pimped it right out. New forks, single speed conversion etc. I had a good $2000 into that bike. I was always very careful about who used it and made sure it was always locked

Anyways, I sit at a little rest stop and some kid probably 15 or 16 bikes up on this right nice giant (brand) bike and shoots the shit for a second. After complimenting my bike, he asks if he can try it out and says I can hold his bike as collateral. Now I usually don't let people use my bike but he insisted. I gave up and said he can do one run down the hill. Well, once he was gone for about 30 seconds, 2 other young teens and a very pissed off father approach me and even try to assault me. After calming them down I find out the oldest kids giant bike was just stolen right from a bench at the park not even 15 minutes ago. And I bet you can guess whether or not he came back from his one run down the hill.

Can you give me the gist of the text in a nutshell?
<bot>: Let kid use my bike and held his as collateral. Turns out his was stolen 15 minutes before and he was ditching it for my nicer bike.