I have assumed you are working with a two-stroke. If I have assumed incorrectly, please let me know. I think this page might help some:
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From there you can also toggle to other install related pages.
There are also quite a few threads here, in which our more experienced forum members go into greater detail on the finer points of adjusting the various controls. You'd have to do some digging with the search function, but it always seems worth it to me. Wealth of knowledge here. That's why I joined.