I think it was in the summer of 1975 or maybe the summer of 1976 when I saw bike helmets in a catalog. It was the catalog of the American Youth Hostels NYC branch which had a small store. They were selling the Bell Biker and an MSR helmet intended for spelunking or mountain climbing. They said the MSR helmet was hotter than the Bell. In approximately the summer of 1979, at the age of 18, I bought a Bell Biker with my own money, which is to say helmets were so rare that my parents didn't put any pressure on me to wear one. People thought I was silly, but I didn't mind.
The Bell Biker was heavy, 17 ounces if I remember right. It was also very hot. Those air scoops didn't work. The shell was made of Lexan™ which is very strong.
A few months later, my girlfriend was riding at night across campus and ran into a chain she didn't see. She got bruised and realized a helmet could be a good thing. She stopped ridiculing me for wearing a helmet.
In 1981, I took a 3-month trip through Europe on my bike. Helmets were even rarer there than here. People laughed out loud at me.
In spring of 1982, wearing my Bell Biker and riding to work, I got hit head-on by a car. All I remember was riding my bike ... and waking up in the hospital. My helmet was damaged, and my bike was mangled. I had a concussion, bruises and a small laceration. I replaced the helmet.
I should be a poster child helmet advocate but I don't put pressure on people to wear helmets. Even though it seems evident that withstanding the ridicule and heat saved my life, it annoys me how people imply that wearing a helmet is the most important thing a cyclist can do to stay safe. It's not. Skill is the most important thing, including handling the bike, understanding traffic, being predictable, and predicting others. Sometimes I get on a bike and don't happen to have a helmet, and I don't think I'm doing something stupid. I do recommend helmets if asked, and I don't scold helmet-less riders.
Here I am in around 1983 in my second Bell Biker.