Either way (rich or lean)Could cause vibrations though they are different in behaviour a bit. On that motor in that heli low needle of around 1 3/16 to 1 1/4 should be in the ballpark and high needle of around 1 9/16 to 1 5/8.
If your too lean it could ni ni ni more and the tail can shake, if its too rich it can burp more and the tail can wag.
Best way I can describe it in words. Also if too lean on the low it can overspeed more easily when you come off the collective on the back side of loops.
Are you free today in the afternoon? I got all my electrics charged (gassers are parked for the trip to NY tomorrow) and will stop by for 3 flights on the way home from lunch with my brother.
MA 1005 Hanson 280, 4170 flts
Spectra 27 3DMax, 3236 flts
Whiplash V1-2 Hanson 300, 1492 flts
Whiplash V2 Hanson 300, 282 flts