I remember back in the 80s (?) references to Konig powered racing sidecars, and that the engine was originally designed for use in boats.
After I found the photo of the solo racer, I did some digging and found out that the engine was a 500cc flat four two stroke with a belt driven rotary disc valve arrangement (more about that later). What surprised me was that it was an outboard motor and I found this picture of one in its 'natural habitat.'
With the engine laid flat you can see the rotary disc on the crankcases.
When used in a sidecar the engine was installed the the cylinders 'fore and aft' and connected to a Norton gearbox by a primary chain.
This picture is taken from a website about the restoration of a Konig outfit. There are lots of pictures of the engine internals, so look there for more technical information.
Now onto the solo. Between 1969 and 1973 a solo Konig was built and campaigned by New Zealand rider Kim Newcombe.
Kim and the bike become very competitive against the factory teams, and were one point away from winning the World Championship when Kim was tragically killed at Silverstone. He was posthumously awarded second place, splitting Giacomo Agostini and Phil Read. (More here).
A replica bike was built by the team mechanic and here's a bit of video about it with him explaining some of the technical details:
Here's piece of video with Kim's son Mark talking about his father, and includes film shot by his mother at race meeting. Also, a really good piece of motorcycle sculpture in Berlin at the beginning.
There is a documentary 'Love, Speed and Loss' about Kim, here's the trailer
And it's available on DVD. Start dropping hints as to what you want for Christmas!!