how on earth is the mag wired in to provide a spark - I can't see how that could work. But I do confess to being pee-poor at electrics. Preferred iambic pentameter to resistance and multimeters at school. Still baffled by the twilight world of Joe Lucas, Prince of Darkness.
Very pretty looking machine you got there Crispin
Everyone calls a K2F a magneto but in the strict sense of the word, a magneto is just a device that makes electricity and does just that.
The K2F on our bikes contains a magneto (the square shaped part opposite to the points side) to generate power for the spark.
That's why you don't need a battery or other external power source. The magneto generates low tension power, which is transformed to high tension by the opening and closing action of the points, and it's this high tension you need to generate a spark.
This high tension is distributed to the spark plugs by means of the slipring which is driven by the magneto shaft.
The slipring is made out of a non conducting material and has a bronze insert that passes by the pick up carbon brushes and thus sends the high tension to the correct plug.
The condenser is just there to prevent the points from arcing, as this arcing would otherwise wear them out fairly quickly.
It's known that bad quality pickup brushes can leave a trace of carbon all around the slipring so the whole circumference of the slipring becomes conductive. The spark will then follow any path and end up god knows where...
Remove the rear pick up brush, and have a peek in the hole. If there's carbon on the ring it will be clearly visible.