For your consideration, here is a frontal view of my TR25/BSAB25 250 MPG bike that set a record of 100mph at Loring and 95 mph at World of Speed (SCTA). It should also be legal at AMA and would exceed the record, but I don't go to that meet any more.
What is important to realize is that there are two aspects of aero drag which are frontal area and coefficient of drag. In this view, you can see that a headlight in front of me, although legal, would not decrease the frontal area. What is important is to get your hands, back, top of helmet, and feet tucked in to decrease that area. And as you can see, my feet are sticking out in the wind, which is not good.
But coefficient of drag is dependent on shape and on anything that can drag in the wind. So I should be able to decrease my aero drag by getting rid of those cables, getting my feet tucked in, and getting rid of the gauges which are all creating drag. I am contemplating adding a headlight with the tachometer mounted into the back of it. This is not specifically disallowed, and remember, don't anticipate a rule that is not written. Just make sure that you are prepared to remove something if necessary to satisfy the inspectors.
The rear end of this bike has no aero improvements except enclosing of the rear wheel (wheel discs). The rules are different between AMA and SCTA, so there are several improvements I can try at the back.
So I will be back (when they open the borders!)
Comments are welcome.
Tom