You know how to do that at 12. And I don't know how to fix this at 32. Funny, what can I say. I tried to fix it 3 years ago, that's when I learned to ride a bike. Hard to fix a flat tire. Now I pay money to the workshop. What you show here is helpful. But I'm afraid: if I remove the tire, I can't put it back. The same thing happened three years ago, I broke my nails by the way. Sorry for my English. It's a second language for me.