What's the newest on 4 stroke motors for trikes?

[JvTonder]

Looks interesting, but rather unfortunate that such short props are matched for use ie: 54 or 56 inch diameter. This severely limits the variety of airframes one can use this engine for. Clearly their main objective was to enhance the performance of their own line of aircraft.
J

Remember the Aerovee can swing the same prop as the Revmaster, ie direct drive. The size they use is just the correct one for the Sonex.