bullpeters:
Try to find photos of the Olds Vertical Gearless - hit and miss engine. This engine uses a simple, reciprocating weight/pendulum on the end of a lever arm, to unlatch the exhaust valve, and also uses a simple ratchet mechanism to index the cam that works the exhaust valve....no 2:1 gears. When this engine speeds up, the up/down motion of the weighted governor-arm, unlatches the exhaust cam until the engine slows down....I think. Anyway, it might be worth giving a look. Maybe you will be able to figure out how this indexing contraption works. Forum Members....how does this indexing mechanism work?
Also, if I remember correctly, one of our forum members recently, came up with a gearless, hit-and-miss, ratchet-indexing mechanism. (Search: 2/17/13 postings by "chicken"/Alex...."Gearless, Hit-and-Miss engine". Videos show engine, and gearless indexing....but, he has balls.
Frank