They’ve experimented from time to time with hubless wheels, which allow for a lot of flexibility in passing bits of the bike through the plane of the wheel when folded, but it’s never clear how they deal with shock - potholes in particular.
Spoked wheels have partial failure modes and those are important.
I wonder too if at these small dimensions you still want to copy the Brompton model, where a flick of the elbow practically assembles or disassembles the bike. Would a design that requires both wheels to be removed and reattached be more workable? Though removing rear wheels can be complicated greatly by the drivetrain.
The front wheel needs to be bigger I think. Not for comfort but for safety.
This makes me want to design one. Roughly, bigger front wheel, hard (no pneumatic) tyres. Suspension on the rear wheel; a low unsprung weight would make this effective.
It reduces the use case to short distances, not commute rides. But that's ok if it's small enough folded to be taken on a train/bus/taxi.
