JohnnyImport

That is a great article I especially like the part about the drawbacks of using "VI" in oils. So I am definitely of the opinion that stretching the 10w down to 0w is a bad idea! Great while the oil is fresh out of the bottle but how long do they last.

Although I am not convinced of the front side numbers, I definitely agree with everything you have stated regarding the benefits of running synthetic oils and running the lightest weight oil recommended for the application as 30 weight oil will have less drag on mechanical components than 50 weight. I am just not sure of stretching down to a 0w over the recommended 10w. Great info you have provided and even if people run only the recommended 10w30 it will still be better than heavier oils and plenty safe within manufacturers recommendations!

I am sorry to report that I am not educated enough to articulate my point after reading about oil, it can make ones head spin! However I still believe that if a manufacturer calls for 10w30 it will be better overall for the vehicle motorcycle or car to stay within that spec. To say that 0w30 is the same as mono grade 30 weight oil isn't exactly true, multi grade oils that are closer in number such as 10w30 over 0w30 are more stable, so once at temperature will offer better protection, I think for my money, using your application sheet I would run 10w30 and let the motorcycle come up in temperature before riding. Also I must disagree 0w has nothing to do with quality or technology of oil just viscosity index. Oil is way more complicated than hot and cold pressure, based on viscosity indexes

Not saying don't use 30 weight oil but switching from say a 10w to a 0w might not be the best idea. Cold engines don't need to make max horsepower there are other concerns besides throttle response etc. so a modern 10w will have all the benefits of a modern 0w, because most of the technology in oil is part of the additive package added to base oil stock. Just to clarify this is great information and props for doing all the leg work.

Just read this post and the info is great but only viscosity and oil pressure at temp are being considered and although I believe that the newer oils will have better aeration and oxidation properties what about film thickness and sheer points which are what is critical in"high speed engines", I would still be vary wary of straying from the recommended oil. Synthetic over conventional oils will generally provide better qualities for high rpm applications. As wear increases in an engine and tolerances increase the thinner oils will not provide the same protection.