What's the best 4 cycle break in oil ?

[michael whiteman]

It's about time for a new engine and wanted your opinion.

 

[Gordy]

I personally ran ZDDP in some Valvoline 10w 30

 

[ImpulseRocket]

Any clean standard oil and a little zinc additive go a long way.

 

[Darwin]

New cars come with full syn now standard from the factory. Tolerances are so tight I'd stick with that on a Nippon motor. Chinese clone I'd use dino oil for break in, usually 10/30.