I found this on Leatherup's site:

Several years ago, drawings of a trike on a patent application by Harley-Davidson appeared on the Internet. The drawings depicted a leaning trike – a vehicle with a suspension system that allows leaning while cornering, just like motorcycles do. Recently, it turned out that Harley even made several prototypes of the mysterious leaning trike. The prototypes, powered by a 45-degree air-cooled V-Twin engine, were produced under the code name Penster and designed by legendary custom car builder John Buttera.
The photos with the orange trike show the final prototype from 2006which is now displayed in the Harley-Davidson museum.






CanAm would have been in a world of trounle if this ever saw light of day!

 

It needs flamethrowers.

 

Don't recall what show I saw it on but I recall seeing a trike with an articulating rear end at some rally. Never seen it since but thought it was way cool. A person with the skill sets needed could build one, I imagine.

 

Was it a "tiltster"?
http://www.mysterydesigns.com/tiltster.php

 

icecaps, Yes sir I believe that is the one.