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Be prepared for 10 different answers from 10 people....
I use Mobil 1 in all my SHOs, and have for years. 0W30 in most, 0W40 in the ones that I know have larger bearing clearances.
The most important thing is to pick one brand of oil and be consistent - the greatest risk is when changing from one brand to another, since some additives of one brand don't play well with some additives of some other brand. Just pick one that you like and stick with it.
Castrol GTX 5W-30
Castrol GTX 5W-30
I run amsoil synthetic 5-40 diesel oil. The diesel oil's have all the zink and friction modifiers our engines need that a lot of new age oils don't have. If you don't use the oils with enough friction modifiers in it, you'll wear away your cam lobes. Stay away from energy conserving SM rated oils.
SM oils are fine.
use the proper viscosity as recommended by ford/yamaha and change it every 3k and you will be fine.
you can use any brand of your choosing.