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PCX air scoop ???

Posted: Fri Apr 01, 2016 2:53 pm
by easyrider
Between the windscreen and the front headlight fairing there is an opening fashioned like an air scoop. Wondering if that has a purpose aerodynamically or is it just about design. This air scoop allows air to flow on the inside of the windshield especially when you add a mid or high rise screen to the bike and not sure if this air flow passage has a purpose to it or just a beautification feature. Thanks for comments and thoughts.

Re: PCX air scoop ???

Posted: Fri Apr 01, 2016 3:30 pm
by jblye
I've heard and read that the air scoop "hole" lowers back pressure on the
back side of the windshield so that the front of the windshield lifts
air higher and reduces turbulence.
Whether that's true or not, I have to admit that I really don't know.
My Givi D1130ST tall windshield has the air scoop, and I
can feel air flowing upward on the back side of the windshield
when riding.

In the words of the great comic Brother Dave Gardner:
"I know everything, but I don't know that ! ".
Johnny

Re: PCX air scoop ???

Posted: Fri Apr 01, 2016 3:38 pm
by Jge64
Exactly what I have heard too, I think BMW does it too.....

Re: PCX air scoop ???

Posted: Fri Apr 01, 2016 4:15 pm
by Mel46
We have blocked that hole in the winter to help reduce the cold air, but I have also heard about it lowering the back pressure, so I don't know if that is a true statement or not.

Re: PCX air scoop ???

Posted: Fri Apr 01, 2016 5:03 pm
by easyrider
Interesting.. I have also read that the air scoop allows air to come up on the inside of the shield which would neutralize the pressure differential in the riding pocket. If the scoop hole gets blocked then there would be a partial vacuum(negative pressure) formed in front of the rider hence creating more rider noise and turbulence because the air wants to rush in and fill the vacuum.Just don't know how the dynamic would work on a tall windshield. I can't do a reliable test because March around here is windy as hell and blows every which way .

Re: PCX air scoop ???

Posted: Fri Apr 01, 2016 6:17 pm
by honkerman
Yeah, it's an airflow thing. Can't be certain it makes a huge difference because of the size of the machine and the speeds of which it is capable, but the engineers had a reason for it.

Re: PCX air scoop ???

Posted: Fri Apr 01, 2016 6:58 pm
by homie
That's so you can drop a dust cloth down between the dash and windscreen and run back and forth a couple times. Without the hole how would you get that cleaned up... silly people :lol:

Re: PCX air scoop ???

Posted: Sat Apr 02, 2016 10:58 am
by j.d.b.
It's a good aero-trick for relieving low pressure behind the screen(and load). If you put your hand out slightly above the top of a tall screen(at speed) you can really feel the up-flow of air from immediately behind the screen. I like NOT having that big, upward swirl as on old-style unrelieved windscreens. On my old gear-bike that swirl was always pushing my helmet up and back.