I don't remember seeing too many in the '90s....they were big in the '80s.
they did provide some x-tra cooling....and there was a "cool factor" about having them too.
Thanks for the info Fox. Had no idea people ran them in the 80s too. The ones I've seen mostly look like this.
They look horrible IMO.
I found this piece of info on another site. Interesting test PC has done, but wonder just how much it improved anything. Glad to just know now, it's weird how these small things sit in my mind sometimes.
"FRONT NUMBER PLATES: AIR FOILS AND THE DRAFT
Team SplitFire took their bikes to a race car aerodynamacist to have them analyzed. The first thing he told them was to get rid of the front number plate. The car designer said that the broad curved shape of the front number plate created an air foil that decreased the amount of air going into the radiators by 30 percent (much like the windshield on a convertible creates a back draft that blows your hair forward instead of backward). Pro Circuit/SplitFire team manager Mitch Payton had a wire mesh front number plate designed the next day.
What else did the aerodynamics expert say? Shockingly, he said that with the rider on the bike, the exit vents on the radiators are inefficient. Even if you scoop more air into the radiator wings, it will not cool the engine one iota more if it can’t escape. To get more air in, you have to draw more air out. The car guy recommended air scoops, tubes and vents—all of which are used on race cars and road racers—but will not fit on a motocross bike. Team SplitFire is looking at enlarging the exit vents on its radiator wings."