Hi all, to Measure Twice, Whizzer did not make the two stroke Twin you saw, they were sold by Jack and Heinz, Marmon, and Monarch (called the Super Twin by Monarch). I believe that the engine was actually built by a company called "Power Products".
They were competitors in the day (a bit before my time). I've seen them, but never owned one.
There was one at the Whiz-in up here about spring of 2012, running, no silencers in it, VERY loud piercing noise!
They were a bit faster than the H, but no match for the later Whizzers I'm told.
Mike