Author Topic: Eliminating Back Pressure  (Read 1233 times)

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Offline 46Alpha

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Eliminating Back Pressure
« on: May 29, 2012, 05:51:55 pm »
I've done a quick search and can't seem to find something that address what I'm looking for. I'm very happy with the stock windshield on my '11. I'm 5'10 with a 32" inseam and the stock is perfect for me. But the back pressure on the highway is getting annoying. Is there any way to eliminate this? I'd hate to buy an aftermarket as the stock looks best to me and does it's job.

Offline The Pope

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Re: Eliminating Back Pressure
« Reply #1 on: May 29, 2012, 06:17:19 pm »
Yes, but you may not like the answer.

The low pressure that is created behind the windshield is what cause this. Some have added holes to their stock shield to allow more air to come thru and flow up the inside surface, which helps to eliminate this low pressure. I remember one person that drilled six (3 on each side) 1" holes into their shield just to the inside of the mounting arms. So look at what some of the aftermarket shield manufacturers are doing and decide whether or not you want to attempt modifying you shield.
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Offline fartymarty

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Re: Eliminating Back Pressure
« Reply #2 on: February 03, 2013, 07:17:09 pm »
I'm very happy with the stock windshield on my '11. I'm 5'10 with a 32" inseam and the stock is perfect for me. But the back pressure on the highway is getting annoying. Is there any way to eliminate this? I'd hate to buy an aftermarket as the stock looks best to me and does it's job.


I've have the same problem. (5'6.5" 32"inseam) I had hoped the MRA spoiler would help with the problem. It didn't, although it did provide better windshield performance in very heavy rain when flipped up.
I made the cut in my stock '10 similar to the Calsci vent, and have tested it for a few months. It helps a little with the back pressure, but not enough. I debated ordering a MRA or a Calsci and yesterday I finally ordered the Calsci medium. According to the Calsci site info, it should be about 1 3/4 to 2 inches taller than my stock. If it's too tall I'll just cut it. If the new Calsci solves the problem then I'll continue to modify the stock 'shield to see if I can fix the problem with it. There seems to be considerably less material at the bottom of the Calsci, so maybe that will be the next cut on the stocker. It could be that the little flip at the top of the stock screen is what is causing the back pressure problem. If so then I guess it'll end up being cut down into a summer shorty, or perhaps become material for some home made hand wings. Time and money will tell. ::)
I'll report back.








« Last Edit: February 03, 2013, 07:18:45 pm by fartymarty »

Offline 4Cedars

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Re: Eliminating Back Pressure
« Reply #3 on: February 03, 2013, 07:37:26 pm »
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