Obviously any subject like "what is ____ "will be problematic. I am not knowledgeable about art; I've had a course or two and I do visit museums, but I'm a long way from being a subject matter expert. That said - I have to disagree with IAB (acknowledging that he's surely more knowledgeable than I) for a few reasons.
1. When I go to the Philadelphia art museum, I do see "craft goods". Plates, cups, engraved weapons and even furniture. I've seen goods at other museums as well.
2. Goods can have an aesthetic, non-functional component - and if those components are an expression of beauty for the creator and purchaser, they have an artistic component. The design on a plate is not a function of its job as a plate.
3. Art is, ultimately, a form of communication. Sculpture, literature, and paintings are all communicating something from the artist. The ornate lugs on a Brit bike are designed to express something, or to catch the eye. They're totally unnecessary from a functional standpoint. A paint scheme is designed to catch the eye. They have an artistic component.
4. I disagree with the "critics define art" comment...they're often years behind the ultimate view of history. See Henri Rosseau. I'm no populist, nor do I think everyone's view is equal, but what ultimately decides art is the consumer willing, or not willing, to invest time and money into that communication. Is it influenced by critics? Absolutely...but the citric is the tail, not the dog. Picasso is Picasso because people value him and will pay money to look at his work for 20 minutes in a museum. There are people willing to pay money to appreciate the feelings that a special bicycle elicits.
5. Other artists often have the keenest insight into art...like Henri Rosseau being promoted by Picasso. I would say more so than critics. Many artists use goods to express something about society, beauty, themselves, etc. The level of modification may vary, but the everyday is a component in a lot of art. Picasso bull head.
6. There are acknowledged artists who have used bicycles as a canvas for paint schemes...so they can be a canvas. Is a Pegoretti scheme that different?
In summary, a bicycle is not a painting, and it doesn't belong in a museum dedicated to paintings (unless perhaps painted by a renowned painter) but that doesn't change the fact that creator and purchaser are having some form of communication about beauty, or passion, or speed. There are bicycles with artistic components, and we struggle over our bar tape, saddle and housing choices to make something beautiful. Does it have the sophisticated communication of a Dali painting? Obviously not...but there is an artistic component.
There's so much misplaced reverence for other people's views on what constitutes art when it is really and properly an entirely personal thing. If a bicycle between your legs or hanging on a wall does it for you, then it is art.
"I bet you'd do the same if they was you." F. Zappa
What about passion? If someone spends the time to post over 6000 comments on a bicycle forum in seven years, hopefully they have a strong passion for those bicycles that goes beyond putting in miles every day. No?
Seek: Early 80's Mountain Goat Bar/Stem Combo.