Made $3000 a year then too! In the art world, there is a saying, that everything original starts out as copying something. It's the tweak you add yourself that matters. Of course, if you don't sell your art, then you can be as original as you like. I do hope people copy my longtail. It was soooo easy. Though I used a bike with a steel frame for the rear section, and welded it, I see now that the way mine was put together it could be alloy. You'd weld the bb shaft to the steel front frame, then use some kind of bolt through such as your pic to support the connection at the seatpost.
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