hi
i am getting a new 33cc subaru 4 stroke.
does it run out of the box, after i put in oil?
is there a break in period?
It should, and 'yes'. The manufacture should specify how long that is.
i read it may get better performance after 150 miles on it???
Yes, after it is broken in.
do i vary the speeds for few tanks?
Yes, speed, and rpm.
when do i change oil?
That should also be specified in the manual or instructions that came with it.
yes, i am a newbie...