BMW K1200 feels unstable...

After 3 months on my new K1200GT, I can honestly say it has only been fun. Since most of my time on the bike is spent
with a pillion on the back (wifey) I am sensible most of the time.

I have noticed one slight drawback on the bike, when travelling at speed by myself with the screen extended about half way- I can feel the air pushing against the Top Case and lifting the bike.
I can only say it scares the living daylights out of me! I have not noticed this when travelling with a pillion on the back.

If you have experienced the same, please let me know.

Ride Safe,
TheBikeNut