Windshield noise

[AncientMariner]

Brent,

Thanks for posting the pix of your ingenious solution.

As the weeks count down to my R1200R's build day, I have been reading about the windshield issues with increasing concern. I think I will sleep much beter tonight.

Bruce Ferguson

[Mollygrubber]

Now THAT'S what I was trying to do, but using both bolts on the headlight nacelle for strength, which meant it would not clear the tank.

Your solution is elegant and nearly invisible, and I predict will be copied and refined many times.

Do you think that the single attachment point has the strength to resist pummeling winds at hyper-legal speeds?

Not that we'd ever do that...

Nice work, thanks for sharing!

Peter

[azimuth551]

Thanks for the comments. Maybe I should have made a patent on these and sell them for an outrageous BMW price instead of the $5.00 and two beers it took to make them! I can tell you that it will hande a lot of wind. I went over 100mph for a minute and not an issue at all. I don't normally ride like that, I was testing the whole system. Its not a big foot print so you do not notice it. Yes it might need some tweeking here and there, time will tell. I am glad I could finally share this with you all.

Brent Slater

[celticus]

Brent, I'll send you $10 and a whole six pack.
Good thinking. Good work.

Mark

[AncientMariner]

After studying for hours Brent's neat wind solution and imagining how it will look on my R1200R (once it's built and delivered), it is tatood on my mind.

However, there may be an even more elegant solution that emulates in part Brent's wind deflectors. While studying the Parabellum site to look once more at their Scout Fairing (which I just don't want), I noticed the listing for their "New" BMW R1200R Sport Shield. It measures 19.5" wide x 24" high. It slopes backward at about a 20 - 30 degree angle from vertical. More importantly, it attaches to the headlight mounting bolts and continues downward an inch or two below this mount. This lower extremety also overlaps the opening at the front of the tank that appears to be the cause of at least part of the wind noise and buffeting.

It appears to me that this shield offers both Don Eilenberger's slanted screen due to 1.5" spacers, and most of the coverage of Brent's wind vanes.

Searching the forum I find that Dansti, edward1981, and dlemisch reported installing the Parabellum Scout Shield (PSS). Has anyone else followed suit? Do you 3 PSS users still like your result? Since it will be the middle of winter when my bike gets here, should I order the PSS now so it will be here waiting when my bike arrives?

[gezerbike]

I'll be picking up my R 1200 R tomorrow and have been reading this forum extensively for the last 10 days or so and thought I might chime in here. While new to the R, I have owned about 11 BMW's over the years and have struggled with this windscreen thing for years. Some interesting posts and ideas. My most significant windscreen mod came when I had my 02 R 1150 RS. I bought a Cee Baileys +2 +2 screen for it and it came with the customary flip at the top of the screen. While elimminating a little noise, the turbulence was unbearable, no matter which position I put it in. So I tool my stock screen and cut 3" off it and put it on the bike. The windblast was to my chest, but the buffeting and turbulence to my head were gone..along with the noise. I sent my +2 Cee Baileys back and had them cut 5 " off of it, also getting rid of the flip. When I installed it when it returned, it was and continues to be the best screen I ever had. I learned the key to quiet was not in how high my screen was, but the way it handled oncoming air. Pushing a screen up against it just increased noise and turbulence, as well as backpressure. A flip is a very unnatural movement of air and just increases the noise and back pressure. Goldwing riders for years have raved about the Tulsa screen for it quietness and non turbulence and it doesn't have a flip or other curves. It just moves the air cleanly over them. It is butt ugly though in my opinion. My R is coming with a Ztecnik 18" screen and I'll keep it for a while for cold weather, but I am looking right now at either the sport screen with the spacer mod I've read about or some after market short screen that has some angle adjustability. I want you to know that I do appreciate the time and money you've all spent that should help make it easier for me to find something for me without spending hundreds....or more, on trials.

[xprof]

The Cee Bailey was like being beaten with sticks, the CalSci much better, the CalSci with 1/2" spacer and SAENG swirl edging even better (8000 happy miles that way), but the CalSci raked back even more with some new lower brackets I just made: Heaven!

[deilenberger]

However, there may be an even more elegant solution that emulates in part Brent's wind deflectors. While studying the Parabellum site to look once more at their Scout Fairing (which I just don't want), I noticed the listing for their "New" BMW R1200R Sport Shield. It measures 19.5" wide x 24" high. It slopes backward at about a 20 - 30 degree angle from vertical. More importantly, it attaches to the headlight mounting bolts and continues downward an inch or two below this mount. This lower extremety also overlaps the opening at the front of the tank that appears to be the cause of at least part of the wind noise and buffeting.

Have to go look at that one.. sounds interesting.

It appears to me that this shield offers both Don Eilenberger's slanted screen due to 1.5" spacers, and most of the coverage of Brent's wind vanes.

I do think after extensive shield trials - that the angle of attack is probably the most critical thing in reducing turbulence. I found Gezerbike's comments on the cut-down Cee-Bailey interesting. It does seem as if the flip at the front of the CB screen is designed to kick air up higher, at the expense of additional turbulence. I don't actually mind the air (much - more in the winter, I like it in the summer) it's turbulence that bugs me, so I might start watching Ebay for a used 24" CB and try cutting the flip off the top. If that works there is a possibility we could convince CB to offer it without the flip. Mebbe.

[gezerbike]

While I cut down my factory screen for the experiment, when the time came to cut my Cee Bailey's screen, I called them, told them what I wanted and then sent the screen to them. I think they charged me $25 to cut it and I paid shipping both ways. So I am sure they could cut a new one before it left for that same $ 25.

Well, my new R followed me home Friday and I had a chance over the weekend to get a few miles on it in between the cold rain. I can't say I found the short Z screen to be that bad. Ear plugs and my System IV helmet and it wasn't that bad. A little turbulence but not too bad, but I was able to fell the wind going into my helmets vents, which was good. I bought a BMW sport screen off e-bay last night that I look forward to trying out. Also talked to the folks at National Cycle, makers of the Z technik stuff, about getting a screen to cut down to about 12" to see how that might work. They were receptive to getting me one to try for a nominal cost. Who knows ? One thing I noticed as I played with the R was that it would be real hard to get a good aerodynamic screen on that bike because of the postioning of the instrument cluster as it relates to the top of the headlight...it almost has to go straight up with very little rake. Maybe that is the reason BMW is putting the sport screen on the tourning bike. Anyhow, I can't wait for mine to get here. Here is a pic of the new ride,which will be parked next to my 1100 GS. 2008 with 2,800 miles. Z Technik, Ohlins, Rick Meyer leather seat, powdercoated Motolights, ABS, OBC, centerstand, heated grips and a nice new set of soft bags. Unlike so many of my other previous purchases, this one is pretty well sorted out and ready to just ride


http://gezerbike.smugmug.com/Other/Misc ... 5XKE-M.jpg

[Bodes]

I posted this elsewhere on the R1200R forum bvut this is probably apt.

"I am on my second R1200R by choice, & have done over 60,000ks on the two since 11/07. I am 6 foot tall so that makes these experiences subjective to my size.

On the first R1200R I tried the taller OEM shield. Copped the buffeting straight into the top of my visor - did my head in and I didn't like the look. Got rid of it.

Then I got the OEM sport-shield. Buffetting around neck / bottom of helmet and noisy even with earplugs. Cut down the OEM sport-shield to top of instrument binnacle, buffeting now toward upper chest but still an updraft to helmet. Still buffeting & noisy. Got rid of it.

Now the cleanest air with no buffeting. Allright it can get chilly in winter without 'chest protection' but you just stick a newspaper inside your jacket and that's sorted. Can also get tiring on a long trip (just did a 1,000k trip with only petrol stops) but the trade off is you have an incidental cruise control because it becomes hard work over about 140 k's (87 mph).

Now the bike looks at its best, I get the cleanest quietest air and I won't have to spend another cent on shields.

I'm stoked."

[deilenberger]

Got rid of it.

Now the cleanest air with no buffeting. Allright it can get chilly in winter without 'chest protection' but you just stick a newspaper inside your jacket and that's sorted. Can also get tiring on a long trip (just did a 1,000k trip with only petrol stops) but the trade off is you have an incidental cruise control because it becomes hard work over about 140 k's (87 mph).

Now the bike looks at its best, I get the cleanest quietest air and I won't have to spend another cent on shields.

I'm stoked."

For most helmets - the quietest it's gonna be is no screen. Helmet manufacturers who use a wind-tunnel use it with the helmet alone, no screen in front of it. My Concept-2 is amazingly quiet and buffet free with the BMW sport screen. Problem is - lack of wind protection inhibits extended high-speed riding, which in NJ is a requirement to get me anyplace I want to ride. Plus I do ride in some nasty weather - and keeping wind-driven cold rain off my chest makes it a lot more pleasant and conducive to riding.

Things I think I've learned on windscreen design (at least for my height/inseam/seat-height):

1. A higher screen can result in more noise and turbulence (greater vacuum behind it). It's certainly the case on Cee-Bailey screens for me. The 16" is the quietest, the 20" the noisiest.

2. A big gap at the bottom of the screen may be a good thing (sorta the CalSci idea of breaking the vacuum behind the screen, allowing air to flow up the inside of the screen and join with the air flowing up the outside to create laminar flow instead of turbulent flow.) CalSci has the right idea - just too steep an angle on the screen using the BMW mount and not enough gap under it (with his screen tilted way out at the bottom - it suddenly became amazingly good.. but it still had the barn-door effect in cross-winds and truck blasts - which is why I don't like big screens..)

3. Bigger-angle is better... ie - tilt the screen so the top edge is back more, bottom edge out more. That can combine with #2 for two paths of improvement in one step. It also lowers the top edge in relation to the riders so that may be part of the reason it's better.

4. The cute little flip on the top of CB screens probably is exactly what we don't need. Think of a pitch-pipe-whistle - it creates turbulence (that makes noise) by blowing air across a sharp edge. That's what the flip is doing. Putting the little flip there probably encourages turbulence. I think their idea is they'd "flip" ugly air up higher over our heads. Doesn't work. I'd love to get one made without the flip, but having dealt with CB before - they are flakey to deal with..

5. The BMW touring screen might have the right idea - but it's not tall enough. Dunno if a continuous increasing curve is good for creating laminar flow off a screen or not. Would have hoped they used a wind-tunnel, but it might have been the designers who took the upper hand over engineers.

#2 and #3 are easy to try if you're using a Cee-Bailey with the BMW touring mount (or anything else that bolts up to the touring mount.) LOOK at the bottom mount. Think about what a few 3/4" or 1" spacers behind the mounting point on the bike above the headlight would do.. then go get spacers and some longer screws to try it. You will probably have to put a very slight bend in the top-mounting-arms, but it's not much, and appears to be easily reverseable.

Then go try it.

I've gotta watch for a used CB tall (20") screen - so I can cut the top 3" flip part off, and see how it works compared to the 16" and 18" CB screens that have the flip.

BTW - gotta add - I have no idea of the wind-tunnel effect of the two fork-tube openings in the tank.. since I always ride with a tank bag. I'd feel nekked without one, and actually can only remember once - riding the bike home when I bought it - where I rode ithout a tank bag. So - consider all the above as with a tank bag pretty much blocking the tube-opening-effect others have observed.

[gezerbike]

Well, we had a 50 degree day here in Chicago today and after doing a few Honey Do's I decided it was time to take off the Ztechnik and try out the new BMW sport screen. After putting a 1,00 miles on the R with the Ztechnik, I was pretty sure I wanted something different. Just too much turbulence right in the sheild of my helmet. And it didn't make a difference if I wore the Arai or the System IV. So it took me about 40 minutes by myself to swap them out...must say I like the looks of the bike with the sport screen. And my son agreed..thought it made the bike look more macho, and, as he said, beefier.

It only took about 3 miles of riding to decide that the sport screen, for me, was a better choice. At 50mph and 45 degrees, the wind was negliable, and I did not have on any electrics. At 75 to 85, it was a solid blast to my chest, which was good since it actually helped lift me up off the bars. That same blast of air to the chest with heated gear on will just push that warn gear towards your body, which is good. Stand straight up on the pegs at 60mph and then sit down, the noise in my helmet remained the same, which meant I was in " clean " air while sitting, which is what you look for. So the Ztechnik is packed away and will probably stay there. I have an 1100 GS with an Aeroflow and all the other assorted stuff and it will remain my winter ride. The R has been put away.

The real critical thing here is that when I bought the R, I was also looking at a Triumph Tiger 1050...a great bike. With the Ztecnik screen on the R, I was never that comfortable. The combination of seat hight, screen height and my height, or lack there of, just made things uncomfortable. To the point of almost putting the R up for sale last night and then moving over to a new Triumph. My new, almost naked R is now very much like my old 02 1150 RS, a bike I loved. This bike is just faster, better shifting, better handling, lighter, qiucker revving and , well, just all around a better bike, especially for me at this point in my life. Did I say lighter? It's my opinion that as soon as you realize that the R is not an RT or GS and accept it as it was designed, a naked roadster, the more you will enjoy it. Glad I took the time to swap out that screen.