get the synth out of it & fill it with old school, like the idea you had cheap dino oil
I'm gonna disagree a little with Chris, after 15 mins the rings should be about done seating, but agree that you need to change the oil & get it out of the garage & drive it pretty hard.
this link is motorcycle specific but rings are rings, combustion pressure is what forces the ring to the cylinder wall
http://mototuneusa.com/break_in_secrets.htm
I've also seen cycle related procedure that directs you to use engine braking (decelerating with the trans in gear) during the ring seating process
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