If you used the word biker in the 70's and 80's you were referring to an MC member, no doubt. Lots of folks rode every metric bike around but, nobody considered those guys bikers back then.... only the hard core group were considered bikers.
I started riding in 1960's and your right. We didn't wear the patched leather vests, chaps or any of the pirate uniform you now see most everyone wearing . The only patch wearers and "bikers" were the hardcore 1%ers like the Hells Angels. No offense but as far as I can remember the "family" or veteran MC patch clubs weren't around either, it was 1% or nothing. All we wore then was jeans, T-shirts, work boots and in the cool weather a Levi jacket, or leather bomber jacket. We also didn't buy tons of chrome for our bikes because it wasn't readily available like it is now and the truth is we didn't have the extra money. We used to custom make any parts ourselves and have them chromed if we added any to the bike. Logo shirts were scarce back then but I did own a Triumph logo t-shirt in the early 1970's as I rode a Bonneville and a Trident. I wore it regularly and no one ever said a word about it. It really is funny how things have changed from the old days but I am glad that more folks are riding motorcycles. Yes, I wear HD t-shirts and I really don't care if anyone likes it or not or if they consider me a RUB. Getting someone elses approval is not a priority with me. At 60 years old I'm just happy to still be alive and I do what makes me happy.