Picking up on a side issue from John Manders' thread, (well done, BTW!) I'd been thinking recently about two strokes (TS) & oiling. Several varieties of our Iron Toys are two strokes and built at a time when TS oils were much poorer at their job than they are today. Bearing in mind the task presented to the oil in a modern high performance TS motorcycle, it's a wonder to me that they survive at all, let alone soldiering on for decades at a time with little but abuse and neglect for company.
For instance, thirty years ago, I was always struck by the ability of a needle roller bearing in a TS small end to do it's job without dying in the first five minutes. But they worked just fine and even though the rollers never complete a full revolution, the eye of the conn rod rarely guttered.
I owned several Suzuki 500 TS twins and these had pumped lubrication to the mains (and thence to the big ends) and also to the cylinder walls. The result was the reduction of the traditional wake of smoke behind the bike to the occasional puff upon acceleration as the oil pump was linked to the throttle. Very good idea, too.
Therefore, I grow ever more convinced that the recommended ratio of oil to petrol can be drastically reduced in older engines designed to run on bacon fat lightly cut with paraffin. This year, I'll put my engine where my mouth is and try it. My next side project is a spare Homelite engine I found at the Sortout last year, so there's summut I can practice on!
Perhaps I ought to mention that oil takes up combustion space, so less oil will mean a richer mixture, just as too much results in a weak mixture.
I'd be interested in the thoughts of the esteemed Eric Brain who has had a bit more to do with experimental automotive engines than me ;o))
Man is just an ape that shows promise ...