Ok did my first couple of highway rides on my 13 SERG. Man the windshield is worthless. At 70 MPH i felt like bobble head. My glasses shook so much I couldn't see. Needless to say the windshield search is on , hundred of post later seem like the Cee Baily rises to the top. But man all of these taller windshield (15" recommended, I'm 5'10" 31" in seam) seem like they really kill the lines of the bike.
One thought all RG windshields seal at the front lower edge of the fairing. I notice on my K1600 there was a small airspace that relieved pressure and aided airflow (reduced buffetting?). A friend of mine had a V-Strom and based on forum recommendations he drilled a inch and a half hole at the base of the windshield, pressure gone less buffeting. I have no idea how the physics of this works but it seems to. So to the point, has anyone tried this type of mod to the stock shield ? Any one have any idea why this would work? In reading the posts one of the windshields that seem to work real well on the RG is the Madstad, the Madstad that allows for airflow under the lower front edge of the shield. I don't like the look of that shield but got me thinking.
It's an old idea that's been available on various bike shields for many years (just not on a stock Harley shield). In basic terms what occurs is a vacuum forms directly behind the windshield, and air tumbles in from the sides, above, and below to fill that vacuum. That air is turbulent, thus the head shaking and buffeting. For an analogy, think of how a vacuum forms directly behind a van and sucks road debris and dirt onto the back of the van. One fix is to install an air deflector on the roof that forces air down the back of the van to kill the vacuum. On a bike windshield having a slot at the base of the shield (high pressure area) that directs air up the inside of the windshield "kills" the vacuum and allows for much smoother airflow. For this to work well it needs to be properly engineered, with the correct size and angle of the air intake. Just drilling a couple holes may or may not provide an improvement, and trial and error could get pretty expensive.
Harley is aware of the concept. I had a small quarter fairing on my '99 FXDX that Harley offered in the catalog, and the shield was set up like I described above. However, for whatever reason Harley hasn't seen fit to improve the shields they install on their Touring bikes. In fact, the tiny "looks cool" deflectors they install on Street Glides and most CVO models are actually worse than the larger standard shields in terms of rider comfort and protection. Never forget, with Harley it's all about style, not function.
Jerry