I also found early on that riding without a windshield was too tiring on long stretches of highways. I felt like I was hanging
from the grips.
Watching those weather reporters on TV getting blown around by 70MPH winds? I tell people that's just what I deal with everyday when I ride to work.
I installed a smaller Memphis Shades on my last bike. It did a lot to alleviate the wind on the chest, but it took quite a bit of finagling to get the angle just right to cut down on the buffeting.
My C50 came with a stock windshield that was much larger. The resultant turbulence was truly annoying. At 75+ it would flip my faceshield up.
I had some Memphis Shades lowers installed, but although it was an improvement, it was still far from ideal. I then lowered the windshield down a bit to get closer to the lowers, which were as high as they could go without hitting the turn signals...and...
Problem solved. No, the updraft has not been eliminated completely, but that's a good thing. I don't mind some breeze on hot summer days. But the buffeting is down to a bare minimum and riding is much more enjoyable.
The lowers were worth it, but it all came down to trial and error to get everything adjusted for the best results.