I just returned from another failed search at Walneck's Springfield OH. swap meet and was wondering where people have found swaps that net good returns for other than Harley guys. My favorite is the obvious Mid-Ohio Vintage Race.
In NJ, the Englishtown spring (april 17-19)swapmeet is great for "other than" Harley bike guys. It is a mostly an automotive swap meet but like any motor heads ost of these guys have one bike as well. Last year I passed on several running cb350 and 360s sub $1000 with titles, and managed to buy about a dozen SOHC 750 left side covers for $20. I got a set of 450 carbs for free (the guy didn't want to carry them home) also. IT is more of a car meet but it is huge (bigger than mid ohios swap section) but a lot will be cars, tools, and other garbage. Most of the people at this meet aren't super in tune with the hobby guys so you can get cheap-o deals.
Also I like the White Rose PA vintage japanese swap meet. It is pretty good.
It does seem that most "motorcycle swap meets" have become leather fashion shows. I really like Mid O because of the lack of Harley Stuff, and I ride a sporty too, but my heart is in the Euro/brit/jap bikes and Mid o is the best for that!