What do you mean when you say, "classic" or "vintage"?
Does it refer to a bike that's X years old or older, perhaps 20 years old or older?
Does it refer to all things made before a certain generational change in bicycle and component design, such as pre-click shifters, or pre-eight speed cassette?
Does it refer to something that is now out of production, even if that's only a few years old?
What does it mean?
My first bicycle was a gold, ten speed "Rolls". My second bicycle was a maroon "Royce Union" ten speed. My third bicycle was a white "Rolls" that I loved so much, I bought it even though it was several inches too small for me (21" versus 24"). After that it was a Raleigh Grand Prix. This Raleigh frame fit me properly but was made in Belgium because the Carlton employees were all out on strike.
My current bicycle is a Bob Jackson frame purchased in the summer of 1975. I had it repainted many years ago and the DuPont Imron paint held up much longer than the original lacquer (or whatever it was). Honestly, it could use new paint and new decals but it has a certain "patina" that I like. I am currently cleaning it up and replacing the rusted, worn components with period-correct, lightly-used Campagnolo Nuovo Record components. Unlike many bikes from this era, mine has not been idle for decades. Things wear out with use. Wheels, tires, lever hoods, handlebar tape, and brake pads come to mind. The 1975 Brooks Pro saddle is as good (or bad) as it ever was.
Reynolds 531 Double Butted Tubes, Forks Stays and Blades, for the win!