r u moving in small moves i mean only a screw driver blade at a time and then retesting that is one big key to tuning a gas motor. set the H for max and then start working on the low. ONce the L is set go back and tweak the high it may need 1-3 screw driver blades at the most adjustment to achieve peak again and make sure the motor does not sag for a long run up on the grond long being about 15-30 seconds.....