I drew a quick pic to highlight the detail…

http://scarbsf1.files.wordpress.com/2010/07/motogp_ducati.jpg

and these pics to highlight the different approaches teams take to their fairings

http://scarbsf1.files.wordpress.com/2010/07/motogp_array.jpg

So much for Top Gun!

The Yamaha YZR 500cc bikes had wings too in ’99.
Didn’t help Gary McCoy btw. or was he traveling to much sideways?

It’s not a down force system… It’s a vortex splitter.

The air moving down with the wheel hits air going backwards on the lip of the mud guard, this creates a vortex that hits the bike where the wing is.
This vortex probably climbs into the low pressure zone behind the rider. This probably does no hinder the bike when going straight (even adds speed by lowering drag). But leaning over it probably has a moment of instability when compressed by the ground. The vortex probably switches going over then under the rider being first a “air cushion” then “ground effect” thus loading and unloading the front wheel = high speed unstability.

Actually, making a serrated edge on the front mud guard would be more effective…

In this age of super computers, modelling and calculated fluid dynamics, the punter sometimes forget that some aero problems cannot be modeled or the computer gets it plain wrong. Buffeting chief amongst them.

How do i post a 2 cent picture of what should be done to that mudguard?

G

Aerodynamic downforce is very useful on a bike, just like on a car. The trouble is keeping the downforce, DOWNforce because as noted the force vector changes with the bike’s lean angle.

I wonder if the racing regulations would allow for movable aerodynamic panels? If so, I think we will see before long deployable “wings” on the sides of the bikes that operate primarily when the bike is at a significant lean-angle.

As for the wings, they could easily generate a few lbs of downforce at speed and positioned out front like that even say 10lbs could make a significant difference in keeping the front end plated. At the speeds the bike will reach they may well generate quite a lot more force than that I’d guess.

I would have to argue, personally, that downforce is probably more or less worthless on a bike. First look at how big wings are on cars (like in F1). Then consider how far over a MotoGP rider leans going around a curve. Your wing then becomes very limited size wise on a bike; after all you can’t have that thing dragging the pavement. Where would even you put a wing on a bike to increase your speed around a curve if you were at full lean? Not to mention wings slow you down down the straight.