does cutting a vent hole in the base of a windscreen really cut wind noise?

Discussion in 'Road Warriors' started by spartanman, Jul 14, 2011.

  1. spartanman

    spartanman regret minimizer

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    I have a K75 that I fitted with an R100RS fairing and a taller-than-stock Clearview screen and RT bars (upright seating). The Clearview is quieter than the stock screen but I want to further quiet it if possible. I tried a laminar lip but the buffeting is awful. I've heard cutting a slot at the screen base helps cut noise. I know Aeroflow does this on some of their screens. I've also seen people put spacers to stand off the screen, though I don't this screen lends itself to that mod. Anybody slot their screen? What was the result? Thank you.
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  2. Vertical C

    Vertical C Long timer

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    I had thought that the vents was to prevent a vacuum and therefore buffeting rather than wind noise. Though I expect others who know more than me to chime in.
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  3. LuciferMutt

    LuciferMutt Rides slow bike slow

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    Slots at the base of the windscreen are to prevent low pressure areas behind the the screen. Without a slot, the pressure behind the screen is much lower than in front of it -- this causes the air going over the top of the screen to get sucked down immediately which lowers its trajectory and causes a lot of turbulence (read buffeting) in the air that eventually hits you.

    The slot allows some high pressure air behind the screen which flows up the backside of the screen to prevent so much of the air coming over the top from getting sucked down and to smooth turbulence eddies at the ridge of the screen.

    Slots will only work correctly in a windscreen that has a decent slant. Mostly vertical windscreens will still have a massive low pressure area behind them but a slot at the base won't really allow air pressure to laminar flow up the back of the screen due to the steep angle to merge with the high pressure at the top.
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  4. Riteris

    Riteris Dessert Runner

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  5. kbasa

    kbasa Being, human. Super Moderator

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    An RS fairing? The problem with that fairing is that it shoots the airflow right under your chin, which makes it noisy. You can drill all the holes you want it and it's still gonna be noisy. I had an RS and tried a little MotoFizz lip that sorta worked. I hear that the Laminar Lip actually helps, so you might want to try one of those. I think they're at www.laminarlip.com
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  6. ikonoklass

    ikonoklass Kountersteering Krew

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    Laminar Lip is a good product. I've put them on at least 5 bikes.
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  7. JamesG

    JamesG Rabid Poster

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    You could just slow down. :1drink
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  8. mngl1500

    mngl1500 []

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    I have had Goldwings with and without vents in the windshield. I do not notice one bit of difference in wind noise. The only difference in more cool air coming in. The Goldwing vents you can control if they are open or closed also for when it is raining or if it is cold.
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  9. kbasa

    kbasa Being, human. Super Moderator

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    I think you're looking for an HD thread, huh? :lol3
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  10. bobobob

    bobobob IN HOC SIGNO VINCES

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    What? :ear
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  11. hoax

    hoax Been here awhile

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    I do know that the first gen FZ1 has no vent and suffered from turbulence complaints. The second gen FZ1 has a vent.
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  12. rocker59

    rocker59 diplomatico di moto

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    vents work. :deal
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  13. rivercreep

    rivercreep Banned

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    Ummmn?! The Op clearly stated in his post that he'd already tried one and that it didn't work.:huh
    I had also tried one on a larger touring windscreen (different bike) and found it to be nothing more than an over priced piece of plastic. What I did find works best is when you get the height/angle of the screen correct to fit the size of the rider and that different helmets also make a large difference.
    Sadly, some windshileds on some bikes just aren't adjustable enough to ever solve buffeting/wind noise problems.:cry

    Good luck! It's one of the things that can drive you crazy.
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  14. cycleman2

    cycleman2 Long timer

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    I used a laminar lip on my R1100R stock windshield & it did cure the buffeting. The trick with windshields is that a lot of times the buffeting is caused by air coming under the windshield. That's why lowers on cruisers are very effective in doing away with the buffeting.

    Try this. Going down the highway, take your left arm and bend your elbow so that it is straight across your chest, move it slowly up and down to establish where the wind is coming from. You'll find that in certain positions it will help you locate where the buffeting is coming from and eliminate it. Then you just have to figure out how to make it quieter.
    #14