Hey,
These guys pretty much nailed it. Go to Towerhobby.com and you can look up the motor and download the manual. From your description your low end is like just a skosh rich so loading up at low RPMs. Remember that the low end adjustments SHOULD be very very small and you are fairly close so try just a turn towards lean about the same distance as the width of the slot on the screw. Being patient will get you there quicker than anything. it may take several attempts to DIAL IT IN. Once set correctly it stays that way( if break in is complete)for the most part you will only have to tweak the high end a click or two for humidity etc.