stable three-wheeled bicycle

[Apartunis]

A trike with a single wheel in the back is going to be enormously easier to drive.. and also enormously better in cornering..

While this is true, it is a result of low center of mass height rather than wheel layout. A recumbent delta like this:

rides and corners just as well as a tadpole recumbent trike of equal track width and seat height. It can have the benefits of simpler-stronger-cheaper-lighter frame construction, and more parts commonality with mass production bicycles and granny trikes, too.

It is easier to screw up Ackermann steering (two wheels in front) than bicycle style one wheel steering, though neither one is immune to design problems. The main shortcoming of most delta trike steering comes from using a commodity bicycle fork and bicycle-like head angle when a trike does not steer like a bike at all.

Upright tadpole trikes are very uncommon, but they are at least as as treacherous at speed and on cambered surfaces as a conventional granny trike of the same width. They cost and weigh more, though.

 

[MxusMick]

It would be interesting to see the effect of a rear wheel axle that leaned, I have an old motor grader with front wheels that lean for sharper turning, so combined with the odd handling of 3 wheel action, more lean could produce sharper turning if not "maintained"

 

[Apartunis]

It would be interesting to see the effect of a rear wheel axle that leaned, I have an old motor grader with front wheels that lean for sharper turning, so combined with the odd handling of 3 wheel action, more lean could produce sharper turning if not "maintained"

The more multi track vehicles tilt, the more they approach the qualities of a two wheeler. They are never as good at it as a two wheeler. But they cost much more, weigh much more, and use a larger number of special components.