It’s been all of a day or so since last I thought up a new bicycle design.
Today’s invention is a bike frame consisting of three, box-section aluminium beams.
Each of these members has slots in its edge through which the other beams can pass and be secured by a bolt through both of them.
The saddle attaches to the diagonal bar, as indicated, using the same type of joining technology…which allows it to be repositioned. The steering column runs from handlebars to the front wheel down the inside of the foremost beam.
This configuration would be comparatively simple to manufacture and also allow a frame to be re-sized conveniently to fit a large number of different people.
It occurred to me in a dream that I’d seen this years ago…which is largely the same layout, except for embodying adjustability, rather than foldability. http://www.strida.com/