Originally Posted by northernlights

We're talking about a simple modification to an existing design, not building a bike from scratch.

Then do the modification on an existing bike, as I've suggested

Those are fully folding bikes that aren't even for sale yet so their success or failure is yet to be undetermined.
Both look like very high-end bikes that will probably price in the thousands, when and if they become available for purchase, which doesn't meet my criteria for affordability.

Only 1 is fully folding (Helix,...fantastic bike - if it ever becomes reality),...the other is for a rotating handlebar stem & some strange expanding pedals,...

Interesting, but both are $800 bikes which doesn't meet my affordability threshold ( I would put at under five or six hundred US dollars).

With either bike you get what you pay for: strength, quality, ride quality, durability, excellent customer service. I owned a Xootr Swift, and I curse the day I sold it!

I'm a consumer and end-user of bicycles not a producer.