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Discussion Starter · #1 ·
Ok, I'm looking at a taller windscreen, and like the National Cycle "V Stream"mid height unit, but just like the OEM, it has the center cutout and side 'vents'.
Has anyone experience with riding in the rain, and do those cutouts allow a fair amount of water through?
Are they there to reduce buffeting?
Any input would be appreciated.
 

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If by the side cut-outs you mean the shape of the screen at those points then the only reason for them is so that the OEM knuckle guards don't collide with the screen at those points. If you mean the 'holes' at the edges between the clear plastic and the upper fairing then in my experience no water gets through nor through the central cut-out. Or rather it probably gets through but it doesn;t cause the rider or any satnav etc any problems.
The side cut-outs are IMHO the reason for the buffeting and a screen that is able to be wider because it is moved forwards, reduces the buffeting by a huge amount (eg the Madstad)
Mike
 

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I had the buffering issue. Took off mirrors and went for a ride. No issue. Swapped the mirror sides. No issue. Think it's the mirror shapes forcing air back to driver. Before and after shots. Looking at the GIVI or PUIG tall wind screen to reduce wind noise on the helmet. Don.
 

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I had the buffering issue. Took off mirrors and went for a ride. No issue. Swapped the mirror sides. No issue. Think it's the mirror shapes forcing air back to driver. Before and after shots. Looking at the GIVI or PUIG tall wind screen to reduce wind noise on the helmet. Don.
Can you still use the mirrors if you swap them round?
Mike
 

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Yes like you said. I think in general the idea with those center cutout is that not all air gets pushed around the sides of the windshield which would cause even more noise similar to when you pull down the window in your car. The air starts pulsing and gets much more turbulent then.
Also those cut outs look more modern and cooler than a fully closed windshield, not every design detail we see on our bikes are designed for function. And do not forget the frame which holds the windshield would have to be stronger without those cut outs and that is a weak point on the AT anyway.

However the buffeting issue on the Africa Twin is mainly caused by the air coming up from the fork tunnel, check out my video which explain this a bit more detailed and the solution we offer:
http://www.swegotech.com/Forkshield-Africa-Twin-CRF1000L-stop-ADV-helmet-vibrations.html
 

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Yes on the swap of mirrors. And already did fork tunnel before first ride. No drastic change. Here are fork tunnel fix. Before then afters. Thin diamond plate aluminum. I'm a fabricator. Why Picts are turned I have no idea.
 

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Yes like you said. I think in general the idea with those center cutout is that not all air gets pushed around the sides of the windshield which would cause even more noise similar to when you pull down the window in your car. The air starts pulsing and gets much more turbulent then.
Also those cut outs look more modern and cooler than a fully closed windshield, not every design detail we see on our bikes are designed for function. And do not forget the frame which holds the windshield would have to be stronger without those cut outs and that is a weak point on the AT anyway.

However the buffeting issue on the Africa Twin is mainly caused by the air coming up from the fork tunnel, check out my video which explain this a bit more detailed and the solution we offer:
http://www.swegotech.com/Forkshield-Africa-Twin-CRF1000L-stop-ADV-helmet-vibrations.html
Hi Swen,
As per the poster above, the forkshield made no noticeable difference for me. In my case the turbulence was coming round the sides of the screen rather than up the fork tunnel. I could demonstrate this to myself by simply holding my hand where the turbulence was and moving it back to the source. In my case that was the sides of the screens (and the top when I was using the OEM and the OEM touring). That turbulence source was still there when I fitted the forkshield. With the forkshield in place I cannot feel much airflow coming out of the back of the forkshield and without the shield in place there is very little air coming up the fork tunnel and what there is, does not seem to be turbulent.
Mike
 

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Alles, I just removed the OEM windscreen and installed the Honda tall windscreen. I can say with certainty that I didn't know how good life could be aerodynamically on this bike at speed.

Geometry is important in these discussions so let me start with saying I'm 200 cm (79 in) tall in boots. You can add another 3 cm to get to the top of the Arai XD4 I cover my pointy head with. Even at freeway speeds, this mountain of stuff now sits below the turbulent stream of air pushed over the top by this screen. I am now aware of the low level of aerodynamic turbulence I had been experiencing with the OEM screen. It was never troublesome but it was always there at 45 mph or above. It's gone now.

The hole in the lower middle of the screen is designed to partially fill the low-pressure bubble behind the wind screen caused by shoving a fairly large capture area of air to the top & sides. Without this hole there would be large vortices (von Karman street-like) created which would definitely be felt at the rider's position. It also provides cooling flow and will help a bit with gas mileage overall.

If you want to play around with shape modifications to your windscreen you can carefully tape (I've used painter's tape in the past...easy on & off with no residue) stiff plastic or cardboard mods and drive around with them to see what might help or not. The bike becomes your own personal low-cost wind tunnel. Just pay attention to the attachment so it doesn't surprise you by coming off at speed.

Now, a question for the forum at large - why do some people run opaque wind screens on their adventure bikes? Is it to take your focus or attention off the near ground and push it out farther?

Just curious.
 
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(+1) I have also experienced that the addition of a relatively rounded rider's backpack or a "bulbous" rear top box completes the trailing air-flow at the back of the rider - particularly at the rear of the helmet. Of course, your experience may vary with equipment, stature, and m/c make and model.
 

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Not sure if this would be a thread hijack or not, but does anybody know for sure if the 2020 standard short screen has a different hole pattern than the '16-'17 standard bikes? I know Givi and all those make short screens, but that's not the question.
 

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(+1) I have also experienced that the addition of a relatively rounded rider's backpack or a "bulbous" rear top box completes the trailing air-flow at the back of the rider - particularly at the rear of the helmet. Of course, your experience may vary with equipment, stature, and m/c make and model.
Serious MC road racers wear humps in their leathers to cut down on the separation drag that would develop from the back of the helmet without the hump. This isn't for the rider's comfort as that separation would up the helmet forces. No, it works to help the bike/rider combination to slip through the freestream more efficiently--less aero drag. The small flip on the rear of the helmet helps with the transition. The teams spend some serious wind tunnel time on this little item. It can be worth a few hundredths on the fast parts of the track.

54452
 

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Serious MC road racers wear humps in their leathers to cut down on the separation drag from the back of the helmet without the hump. This isn't for the rider's comfort as that separation would up the helmet forces. It's to help the bike/rider combination to slip through the freestream more efficiently (less aero drag). The flip on the rear of the helmet helps with the transition.

View attachment 54452
(y)

Thank goodness no AT riders need to wear the hump, eh? :unsure:


Although, I can't count the number of times I have seen sport bike riders in full leather get-up and hump and tampered helmet endlessly crawling along with traffic congestion. Remember those days - congestion?
 

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Although, I can't count the number of times I have seen sport bike riders in full leather get-up and hump and tampered helmet endlessly crawling along with traffic congestion. Remember those days - congestion?
And you know they're roasting in their own juices inside those leathers too. Makes you wonder why they go to all the trouble and expense if it isn't just for the look.
 

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And you know they're roasting in their own juices inside those leathers too. Makes you wonder why they go to all the trouble and expense if it isn't just for the look.
I was told not so long ago from a die-hard leather-clad that it is the coolest thing to wear in the summer humidity.

To this day I still do not understand what they said.

I envision bodily-salt-encrusted leather after half a dozen of such outings.
 

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And you know they're roasting in their own juices inside those leathers too. Makes you wonder why they go to all the trouble and expense if it isn't just for the look.
I have leather jacket from Dainese
Racing 3
Top product.....from 12 till 35 degrees celsius

But lets talk about windscreen
I ordered for my ATAS MRA Vario

Should be like this.But tinted


Sent from my iPhone using Tapatalk
 

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Haven't gotten an answer yet so I'll try again...

Why do some riders run opaque wind screens on their adventure bikes? Is it to take your focus or attention off the near ground and push it out farther? And why is that advantageous? Just curious.
 

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Haven't gotten an answer yet so I'll try again...

Why do some riders run opaque wind screens on their adventure bikes? Is it to take your focus or attention off the near ground and push it out farther? And why is that advantageous? Just curious.
How 'bout an answer from someone who doesn't run with an opaque screen?

One - mind you, minor - advantage I can think of is it helps hide the cabling and trash behind the instrument cluster area providing a more tidy appearance.
 

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On my last bike, CB500X, I coated the inside of the screen with Plastic-dip. Reasons were just for looks as well as keep the sun off the speedo a bit. Nothing about changing focus or anything, at least not for me.
 
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