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Stan, you should know by now that choosing an oil for an air-cooled engine isn't about scientific facts, measurable quantities, or numbers.
It's all about what you just know in your bones is right.
It's a defining decision. Like choosing your beer or your boots.
Some of us think that oil just has to be green to be any good. Others think that if everyone else is using green oil, then some other color is probably better.
Some of us used to know that 20W-50 is right, but now we know that 10W-40 is right. But that could change, depending on what the cool kids are doing.
The problem is that most of us will get bored with our engines before we actually wear them out. And even if we do wear them out, we won't know if the oil was at fault or if it was alloys of an uncertain parentage. Or maybe it was the time we missed a shift trying to teach that Mustang a lesson.
I am glad to see that you're finally taking Musbjim's advice, though, and buying what's on sale. Saving three bucks a quart can mean $15 at every change - maybe more if you've got a dry sump. So, that's $30 a year right there.
Everyone talks about oil, but no one ever does anything about it.
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