I believe you mentioned the idle mixture screws are set at 1-1/4 turns out? That iirc is on the leaner side. I’d richen the idle screws a 1/4 and see if that slight stumble goes away. Then try an 1/8 at a time either way to hone in on it. Ignore the gauge for now, adjust for drivability then If you get near the max range on the screws turned out go up one step lean on the needles or down on the jets. Basically try different combinations on screw settings, and adjust the other stuff step at a time if you get too close to max on the idle screws. Been there done that on a Street Demon 750 (same design) and ignored my gauge at first, focused on drivability and got it licked. Might work for you might not but don’t be set on a certain idle screw setting as being ideal. Gotta search for it