[tooseevee]

I love the smell of burnt castor oil in the morning. It smells like victory!    (Especially when being burned by a big British racing single.    )

            "Duvall Rules" and Coppolla 

[Keef Sparrow]

Don't do it on a modern bike - oil and catalytic converters don't mix. Fuel (petrol) injection systems are not designed for it either. If this was a good idea it would be mentioned in the owner's manual.

[AzCal Retred]

This here be dinosaur country, son... thud...chuff...thud...chuff... - ACR -

[zimmemr]

Don't do it! The idea of the oil control ring is to prevent oil from reaching the combustion chamber. Oil in the fuel will lean out the mixture, especially on a carburetor equipped bike, the oil displaces the fuel as moves through the jets, will foul the plug and stick the rings. If it was required there would be an oil injection tank next to the fuel tank. Yes, I know all about Marvel Mystery oil, it's great for cleaning air tools...

[AzCal Retred]

Wrong side of the piston. The oil control ring applies to liquid thrown onto the cylinder walls, not a minute fraction of oil blended into the fuel. Mixtures richer that 16:1 are the only ones I know of where there is enough oil to begin to affect fuel viscosity & flow rate and necessitate jetting changes. The 100:1 or less blends suggested here just affect corrosion or exhaust smell. In my desert days the sons of affluent folks would run 100:1 or even 120:1 blends in their two strokes to gain some microscopic HP advantage. Daddy was soon replacing crankshafts on Sonny-Boys subsidized racer and the blazingly fast first place experts were still running EZ-on-the-mechanical-innards "low-performance" 26:1 to 40:1 blends. Skill is an amazing thing to watch...

[zimmemr]

Wrong side of the piston. The oil control ring applies to liquid thrown onto the cylinder walls, not a minute fraction of oil blended into the fuel. Mixtures richer that 16:1 are the only ones I know of where there is enough oil to begin to affect fuel viscosity & flow rate and necessitate jetting changes. The 100:1 or less blends suggested here just affect corrosion or exhaust smell. In my desert days the sons of affluent folks would run 100:1 or even 120:1 blends in their two strokes to gain some microscopic HP advantage. Daddy was soon replacing crankshafts on Sonny-Boys subsidized racer and the blazingly fast first place experts were still running EZ-on-the-mechanical-innards "low-performance" 26:1 to 40:1 blends. Skill is an amazing thing to watch...

All your points are valid, especially in the minute quantities you use in your examples, though I might quibble that anything richer than 30:1 had an adverse effect on my Bultaco Astro,'s jetting but that was a two-stroke short tracker, running at sea level, not a desert racer. I still don't think adding any oil to a modern four stroke's fuel is a great idea. But I admit not much smells better than an engine running a genuine racing Castor oil.

[zimmemr]

Here's just the ticket:

Blendzall #460 Racing Castor Lube
The finest race-proven racing castor oil available in the world today. Unsurpassed in quality & performance.
* For use in all 2 cycle engines.
* Cleanest burning degummed castor lubricants available.
* Will not foul plugs.
* Eliminates engine wear.
* Designed for extreme temperatures.
* Blends with all fuels.
* Contains a seal conditioner, preservative and rust inhibitor.
* Contains no acids, nitrates, or rust promoting synthetics.
* Race proven since 1959.

I can't say it'll make your Bullet faster, but any old racer standing downwind will break into a big smile...     - ACR -

It's also a great lubricant if you get stuck behind a guy that's burning it for a lot of laps, and I don't mean that in a good way

[AzCal Retred]

I've read about the WW1 pilots being affected the same way after spending flight time behind their castor oil spewing rotaries...the "clean" air war, eh? 

[zimmemr]

I've read about the WW1 pilots being affected the same way after spending flight time behind their castor oil spewing rotaries...the "clean" air war, eh? 

I've heard that as well. I'll bet there were some embarrassing and hurried cockpit exits. My mother (91) told me that her mother use to make all the kids take a teaspoon of it once a week to keep them "regular."

[heloego]

My mother did that for awhile to all six of us kids. We hated the taste, but there's always "that one kid", a friend next door, who claimed he loved the stuff. Time proved us correct that there was something definitely "wrong" about that lad. 

[Karl Fenn]

I'm sure if this old wives tale had any validity engine manufactures would mention it, the best way to break an engine in is to take it easy, two stroke oil might build up carbon on the piston.