There is a specific section for Classic & Vintage bikes... a much better place to discuss older bikes.

And there is a subsection there to specifically ask about the value of vintage bikes.

You will get the attention of people there that may be able to let you know what the bike is worth. However, one aspect of the value of a bike is where the bike is located. For example, depending on the bike if it is in New York it could be worth 2 or 3 times what it is worth in Iowa.