I am trying to trace information on a model of a Rider based engine shown/described in ME during the late 1980's, early 1990's. The engine featured an inlet valve on the cold cylinder that allowed a fresh charge of air during each cycle. The cold cylinder compressed the incoming air while transferring it to the hot cylinder.
The hot cylinder followed normal Rider practice with the displacer above the piston. It differed in that, at, or around bottom dead centre, there were ports in the cylinder wall, (I think), to allow the hot gases to escape.
I have been unable to trace this myself as I cannot recall the article title, if it was an article. Or it may just have been a photograph from an exhibition. A lead to the article, a copy of the article, or a drawing of the engine would be much appreciated.
Regards
Gray,