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Windshield vent

Has anyone tried to cut (or have a plastic shop cut) a vent in a stock windshield?
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Are you familiar with the vent in G/wing shields ? Those are available aftermarket, various vendors .

They come supplied with the template , hardware , & all. I have installed four of them so far with good results. Just be sure that the intended shield is not 'too' curved. Follow the instructions & you should be good to go. If perhaps you do not have the proper saw,etc ? I would think a plastic shop would be able to do it for you, if you provide the vent / shield etc.
 
Windshield "vents" can help with back pressure and smooth out airflow onto the rider by filling in the low pressure area behind the windshield. This keeps higher pressure air from trying to come in behind the screen, allowing it to flow by the rider further away than it might otherwise.

Windshield "vents" can also hurt airflow! Gold Wings and other bikes that have a fixed screen attached to the fairing do not have air coming under the screen from off the fairing. This is where the vents can do the most good. But, on bikes like the RT/K bikes that have a screen attached to hardware that raises it, there is a lot of air coming UNDER the screen that helps fill in the low pressure area. Adding a vent to these can actually HURT the airflow as it can disrupt otherwise smooth laminar flow that sticks to the back of the screen. Directing the airflow coming behind the windshield on the RT/K type bikes is where the gains are found. I tried every sort of cut out vent, in different positions. I even installed one of the Gold Wing style adjustable vents. Found even closed it disrupted airflow and made noise/turbulence. Still, you never know until you try something!

Be careful drilling holes in these screens, stock or aftermarket. A step drill is safest ( looks like a tree with annular cutter rings ) to use. Cutting can be done with a fine ( more teeth/smaller teeth the better ) tooth jigsaw or my favorite a 4" cutoff saw abrasive blade like you would use to cut metal.
 
Meh. I put two vents in a large Vetter windscreen a long time ago. The benefits were, IMHO, wishful thinking. A few square inches of opening isn't going to do a big job of filling the volume behind the windscreen. Sorry.

If air curling around the windscreen is a problem, better to think about deflecting "wings" that mount along the side of the windscreen. Personally, I think they look rather hokey, but that's just my opinion.

In general, the biggest problem I've encountered is the windscreen area making a nice sail for snagging side winds and being pushed around by turbulent air from 18-wheelers. Not much to be done about that.
 
Meh. I put two vents in a large Vetter windscreen a long time ago. The benefits were, IMHO, wishful thinking. A few square inches of opening isn't going to do a big job of filling the volume behind the windscreen. Sorry.

If air curling around the windscreen is a problem, better to think about deflecting "wings" that mount along the side of the windscreen. Personally, I think they look rather hokey, but that's just my opinion.

In general, the biggest problem I've encountered is the windscreen area making a nice sail for snagging side winds and being pushed around by turbulent air from 18-wheelers. Not much to be done about that.


I think ? There is a vent-v-shield size ratio ? If the vent is a correct / near correct size for the shield it performs well against turbulence .

In the four I have done, they all seemed...different, but improved. I also believe vertical location is a factor. Bottom line IMO allot of luck involved...:dunno

One thing I am sure of....on hot days they do allow some much appreciated airflow....:thumb
 
You can go to an aviation supply house and get the 3 1/4in pop out vents that are an exact replacement for the round vents used on the Vetter fairing windscreens. Carefully cutting the holes is not a big problem if you have the correct size hole saw for your drill.
 
I have the Wunderlich screen with the vent and I like it over the stock screen. I've heard others say it makes a whistling noise but I have never experience that.

Also, There was a guy over on the BMW K1600 forum that would cut the hole for you in your shield. I think his forum name was Vandledog if I remember correctly. You might check and see if he is still doing that.

Mark T.
 
Thanks for the input everyone. That is exactly the info I was looking for. My fear is creating a problem by cutting the stock screen (that was never designed for it) to try and get a little bit of airflow through it. I feel like it does a descent job all around, so I don't want to make it worse, or create some weird buffeting situation behind the screen and make it completely worthless. Hmmmm, I'll have to give this some thought. But thanks for all the good info, I truly appreciate it!
 
You can go to an aviation supply house and get the 3 1/4in pop out vents that are an exact replacement for the round vents used on the Vetter fairing windscreens. Carefully cutting the holes is not a big problem if you have the correct size hole saw for your drill.

That's exactly what Vetter supplied to replace the original yellowed vents.
 
I have successfully done what you are asking about. I simply reverse engineered off of the California Scientific windscreen.
I also removed a total of 5"from the height of the standard GTL windscreen.
It made an amazing difference in air smoothness behind the screen .

These screens are pretty tough , not easily shattered like a Cee Bailey's.
I simply double layered blue painters tape , laid out the pattern and drilled a hole inside to allow the use of a fine tooth plastic cutting blade for my jigsaw.
Go slow and avoid letting the shield start flopping around. You can smooth out imperfections with a fine tooth half round file, then sand out the saw -file marks.
Wash the Screen and Remove the tape.

I burned a lazy afternoon doing mine.
 
CalSci Windscree

CalSci has a hole/vent cut into their windscreens. But it does not increase air flow to the rider, it eliminates the vacuum behind the windscreen; doesn't "pull" the rider into the screen.

Duane
 
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