An article on MC areodynamics

While on another motorcycle forum (Okay, Burgmans' but...) I saw an interesting article explaining MC aerodynamics and some of their challenges. I thought I'd share it here.

http://canadamotoguide.com/2016/05/04/motorcycle-aerodynamics/

What else is there to do when the weather in this uncooperative, right?

It's ironic that they image they use is of a 1200 GS with those jugs hanging out in the wind

They need a better editor though. Drag forces are proportional to the square of velocity, not the cube,

D = Cd * A * .5 * r * V^2

Cd = drag coeff for that body
A = reference area of surface
r = air density
V - velocity

Source

Other than that, it is a pretty good article.

One thing they kind of messed up on though. Turbulent air is not always bad. This is what they were hinting at in the segment where they have the photo of the jet wing. Laminar flow separates from bodies very easily. Once it does, it creates drag. The longer you can keep the air attached to the surface of the body, the less drag you will have. This is why golf balls have dimples. The dimples actually trigger laminar flow separation, creating turbulent flow. However, turbulent flow will follow the surface shape better than laminar flow. The net result is a layer of turbulent flow that actually pulls the remaining laminar flow closer to the surface, resulting in less drag.

Laminar flow can also sometimes setup nasty oscillations. Think of a smoke stack or tall flag pole wobbling in the wind. Sometimes adding small imperfections in the surfaces can trip the laminar flow so that turbulent flow is created and this can reduce the amplitudes of the oscillations.

I like the feeling of a strong flow from behind, riding with the wind.