[flyrider]

I just went out to the garage and played around with X-creen positions, during which process I realized what a dumb question I'd asked. There's no way to know without more experimentation.

So no need to answer. I'll be back if I can find something good here. All this bike needs is some diffusion of the wind, I think, not necessarily a higher, wider or technically complicated solution.

Windscreen threads for the GT are like soap operas...you could leave them for 5 years, come back and the plot will have changed not one iota.

[]

 

[flyrider]

So you're saying you want to make it work like a Madstad works?

View attachment 366865

Exactly! Except without the Madstad. []

 

[flyrider]

"DIVIDE, AND CONQUER"

Just back from a test of the MRA X-creen, performed with a different concept in mind. Wind problems on bikes like the GT seem to center around the turbulence created by the windscreen. In doing some reading, I came to the conclusion that I was approaching the solution to the problem of turbulence from the wrong perspective. I was trying to eliminate wind noise, when that (in reality) is not possible, unless you're in a car (even then you can still hear some noise), or behind a mammoth windscreen that blocks the wind. The problem with blocking the wind is...it gets HOT! That's why I couldn't use the Madstad...it did a good job of blocking wind, but even with the flow underneath it, the Madstad cooked me.

I mounted the MRA and went for a ride, with the idea that no longer was I trying to eliminate wind noise by blocking it, but - rather - I was going to "diffuse" the wind coming into and over the stock windscreen. By diffusing it, I was attempting to "break up" the wind into smaller (force-wise) components, reasoning that if the wind force is LESS, the turbulence would also be less. After trying a few settings, I really got into the diffusion idea and hit on a setting that not only divided the wind striking the windscreen(s), but it allowed plenty of airflow. The clue that I'd hit the "sweet spot" was when I realized my shoulders were no longer tense and my whole body was relaxed; I can tell you...this was never the case before.

With the setting that worked, I tried various speeds...60-70 (prime cruising speed), 80 and 90 mph. The turbulent buffeting was virtually eliminated. I heard the wind, but it was a soft flow, like a smooth sine wave, unlike with the OEM screen alone, which created what I'd call a "sawtooth" noise pattern...very fatiguing and causing much body tension, to say nothing of headaches!

The MRA X-creen might look a little odd on the bike but it doesn't ruin the aesthetics at all, to my mind; the bottom line, though, is...does it work? For me...oh,yeah.

I have the clamp-on, tinted, "Sport" version of the MRA. It looks quite good with the tinted OEM windscreen.

Happy days...[]

EDIT: Adding some photos of the installed MRA, and a comment: I still think the VStream "Sport" windscreen is a better screen than the OEM, but while it altered the wind flow and improved the noise situation, it didn't eliminate the turbulent buffeting entirely. That's where the MRA seems a better solution - the elimination of the fatiguing turbulence.

 

[flyrider]

I have learned to live with the noise by the use of good earplugs.....and either the MRA or Puig deflector on either the stock windshield or the Ermax Sport screen. The deflector does smooth out the airflow, and with my deflector mounted at the tallest position it moves the air from neck level up to my eye level. (On really hot days at slow speeds I can adjust the deflector to blow air down onto my shoulders to keep me a bit cooler).

I will have to try your lower position and see if it works better than what I am currently doing.

I've tried the deflector in a high position and find it only increases turbulence. That's why I started looking at whether a different approach might work...diffusing, rather than deflecting, the wind. It seems to be the case...

 

[flyrider]

Interesting, I have the same screen set up, though clear screen (wonder if that makes a difference ). Mine still creates a lot of noise. Anyway, I've not tried mine at the same angle, think I'll give this a go and see how it goes

Thanks for posting the photos

I previously had installed the MRA and gave up on it...twice. I kept approaching it from the perspective that I needed to get the air "over" my helmet, and to do that the MRA had to be higher. When I realized that diffusing the air flow might lessen the turbulence, I re-installed the MRA and set it as you see in the photos. I did try a number of combinations and always came back to what you see. If you think about how the air hits the screen, you can see that the way I have it divides the airflow...the bulk hits the OEM screen, but at the top portion of the screen, the MRA intercepts the air before it hits the main screen and sends it a bit higher, while air hitting the OEM screen flows under the MRA and does just what a Madstad does...

You mentioned the angle...that is crucial in my opinion. If you look at the side photo shot, you can see the angle of the MRA is the same as the angle of the OEM screen. If I set the MRA even a little more upright, the noise increases.

The key realization I had was that the issue common to the OEM screen is turbulence, not wind noise, per se. With the wind divided (diffused) the force of the wind coming over the screen(s) is lessened and turbulence minimized. I still hear wind, but now I don't have that awful chaotic noise caused by turbulence. I still need earplugs (custom), but as I said in a prior post, the proof that this was an improvement was the relaxtion I felt while riding. Before this set-up, I was always tense in the shoulders...and everywhere...due the discordant noise. Now? Not so much!

 

[flyrider]

I have tried the screen in various positions, those that seem to work best, as you've pointed out, are where the MRA is parallel with the OEM screen. I think it works best as you have positioned now, but I also think it looks better and still works where it is positioned as low and close to parallel to the OEM.

Do you still have the clear OEM screen? I was thinking it would be interesting to enlarge the two cut outs at the bottom of the screen to see if increasing the airflow through there improves (or not) to turbulence as more air flow there should reduce the vacuum created. I know I'm not clever enough with a jigsaw! However, wonder if it's worth finding an engineering company locally who might cut to the same shape, just twice the size.

I do still have the clear screen, and that's an interesting idea. I couldn't do it, but there are companies here that cut plexiglass, so it could be done. But for now, I like what I have. It divides the airflow, weakening the force (and therefore the turbulence), and the space between the MRA and the OEM allows air to flow underneath the MRA, in a way that mimics what a Madstad does (without the Madstad, of course). The fact that I now ride "relaxed" is evidence enough that something good is happening with this set-up.

 

[flyrider]

flyrider,

I see from one of your previous posts that it is the "Sport" version. Where did you get the tinted OEM screen?

Seedman

Sorry for the delay in replying...haven't check in for a couple of days. I got the tinted screen from Sierra BMW.

As for the MRA...I did finally realize that I was probably approaching wind noise from the wrong perspective. Having tried higher screens and finding (as others have) that they create new problems, I decided to give the MRA a try. What I've concluded is that you CAN'T eliminate wind completely without blocking it completely, but when yo do that you get too many complications that didn't exist before. The MRA works best for me angled at the same angle as the top 1/3 of my stock (tinted) screen. It seems counter-intuitive, but moving it more vertical INCREASES the noise level, because what was a laminar flow gets suddenly pushed in a new direction and "tumbles" over the screen, rather than flowing. The gap between the MRA and the stock screen allows air to flow through it, which helps keep the air over the top of the MRA from collapsing into a low pressure pocket.

It isn't perfect...by it's the most elegant solution I've found so far.

 

[flyrider]

fly rider,

Thanks for the info. I know from another thread you had started last year that you were using the V-Stream sport/tour screen. I guess you ultimately didn't enjoy that either?

I started with A Madstad and used that for about a year. Could never get it quite right as I could on the one I had on my F700GS. Then I also tried all three heights of the V-Stream. The sport/tour was the better of the three but still found the wind noise a little loud. At the moment, I am riding the bike "naked" using no windscreen. I simply have the Madstad mounting plate only filling the gap. It's the smoothest air so far but no wind protection.

Perhaps I can give the OEM with the Screen a shot.

Thanks!

Seedman

I liked the VStream "Sport" screen a lot. It created a larger pocket of quiet air behind it than the stock screen, but I gradually became aware that my shoulders were being battered a bit by somewhat turbulent wind being thrown off the sides of the screen. I switched back and forth a few times and concluded that the gain in the size of the calm pocket wasn't enough for me to offset the shoulder problem, and the increase in quiet wasn't as great as I'd initially concluded. HOWEVER...it's a good screen and from time to time I'm tempted to try it again. But with the OEM tinted screen and the tinted MRA "sport" X-creen (which matches the OEM tint nicely), I find I'm quite relaxed on the bike. Sometimes my custom earplugs don't seal as well as they should, and I experience some noise, but overall (as I said earlier in this thread) the objective was removal of buffeting/turbulence-induced noise, and it's done that.

Conclusion: The MRA works well, looks pretty decent and once you tell yourself nothing is "perfect", it's a keeper. I've had the bike to 100 mph with it and the ride was good. The ideal speed for cruising with this combo is 60-70 mph, and that's really a fine speed if you're having an enjoyable "cruise". When I want to beat the twisty canyons mercilessly (well, not exactly, but still...), I take the RR.[]

 

[flyrider]

Thumpin, that's a hell of a write-up...thanks! The effort you've put into this will help others shortcut the process of getting a good windscreen result...