You're kind of beating a pretty close to dead horse changing the clip on the R117xx needle (imo).
Chances of ron putting the stock needle back in after he's done with it are about zip-point. Better chance you have a 'C' or even a 'D' angled needle in the RB carb now.
Lengthen the straight section of the needle. You can make the straight section come on later by lowering the needle, but you haven't changed the relationship of the straight section to where the taper starts (given the same L1). THAT happens only when you change the slope (the oem 'R' needle is a 1º 15" slope, a 'C' is 1º 34", a 'D' is 1º 45", OR 1.25º, 1.50º and 1.75º respectively) of the needle.
A CEL with the stock slide (5mm cutaway) is probably a good starting point. A 6/7mm cut slide would help.
I never did get the low end burble out of my kdx until the slide/needle combo was changed.