Put some masking tape or electrical tape over the bottom edge of the top windshield - see if that affects the whistling.
I get a whistle between 38-45 mph.
The angle and height also affects the whistle.
I just don't drive those speeds....lol.
Cheers,
Steve
My girls:
Isleen - 2014 F6BD
Saorla - 1995 FLSTN Heritage Special
"Politeness, n: The most acceptable hypocrisy."
Ambrose Bierce
Received the replacement lower base plate from Madstadt last night. Look like what they did is just drilled larger mounting holes in the lower base plate; probably to aid in getting the bolts started while fastening it down. And will probably help in taking the "bow" out of the base plate after it has been tightened down onto the windshield mounts.
21 years Army (retired)
...been everywhere, seen everything, done almost everything.
IBA 80537