Here's the deal, sometimes I want to wear a helmet, and somtimes I don't.
But I couldn't wear it when I had the windshield on... too much buffeting.

I tried most of the suggestions to try and curb it but nothing really helped.
I've got the Quick disconnect shield that comes with the dyna essentials kit.

THE SCIENCE: During my rides, I realized that the main buffeting air was coming straight up from the sides of the tank near the rear.
I figured it had to be the way the air was flowing around the lower sides of the shield. My plan was to try and "disrupt" that flow or diffuse it somehow.

FIRST MOD: I bored several 3/4" holes in the lower sides. It helped a smidge but still not great.
The second fix seems to be the one that took care of it for me.
I took a jigsaw and cut the lower section in to within 3/8" from the front stainless strip. Then filed it all smooth.

Took it out for a test and now I can wear my helmet again. Had it up to 70 mph and didn't feel any different than if I had the sheild off.
There is still some air coming up the side of the tank but it must have been reduced.
The only thing I didn't try was having the visor on the helmet.
Regardless, I'm very satisfied.

The thing to keep in mind, is the variables... Rider height, seat position, etc...
Can't say anyone else would be successful, but it worked for me.
I'm 5' 8" and have an 08 LR with a mustang solo wide seat.

I also cut 2-2 1/2" off the top, so I could see over it. Made the top even with the cleft of my chin.

Here's a pic...

 

That's a good idea. Almost looks like a Windvest now

 

You did a great job cutting that!

 

Thanks, believe me, I've had a lot of practice.

Wish I had a bench vise though... would have made it much easier.

 

I actually think it looks way nicer than stock trimmed like that!