Calj737,
So why did you build yours?
The 550 was undertaken as a learning opportunity for my 2 oldest boys. Essentially, to teach them automotive principles. What's better/easier than an air-cooled, carbureted, 3 circuit bike? Plus, I and they, really love motorcycles.
The 500 build is a different animal somewhat. My oldest is now in Industrial Design (Transportwtion Design major) school and we are using it to be a platform for him to learn design, planning, fabrication, etc skills. It will be far more aggressive than the 550 both aesthetically, as well as amped up performance wise.
The 572 is a vintage resto-mod for a friend. I have time and resources, he doesn't, so this one falls under the connecting with family category.
I'm also doing a '74 BMW, it's just not listed here. That's for me. Nostalgia, memories, soul, independence, whatever the reasons. I build them to ride, and build them for keeps. The budgets are off the hook for a vintage CB, but when you amortize it over 20-40 years, who cares? I hope all these bikes are kept in the family and cherished by my sons (and buddy) as long term mementos of our relationship and time spent together doing something we enjoyed (mostly).
I doubt I'm that much different than others. Budgets and styles perhaps, but reasoning and impetus I'd suspect is universal. I just build something I won't ever tire of in my case. Partly why the builds take some time. Design. Change. Design. Decide. Change. Change again. Build. You know how it goes...