Triumph Rat Motorcycle Forums banner

Increased buffeting with Parabellum sport shield

6K views 23 replies 19 participants last post by  rich2009 
#1 ·
I just installed the Parabellum sport shield (medium 20") on my bonnie and took it out for a test ride. The buffeting on my head (mostly above my visor) is so bad even at low speed (< 60 mph).

Anyone have the same problem? Is there any way to adjust the shield?

I am 5'10" with 32" inseam and I can look over the top of the shield.
 
#2 ·
When I first installed my Parabellum, I could see over it and the buffeting to my head was almost unbelievable. I called Parabellum and they exchanged the shield for a taller one. (great customer service) I now have to look through the windshield and continue to have buffeting at speeds over 70mph. I don't have an answer but no one else seems to have the problem. In fact, everyone that has one states that they have had great success. I'm 5'4" by the way. If someone has a solution, please tell me.
 
#3 ·
I don't know about Parabellums, but I do have a sport touring bike ('05 Concours) with a large windshield. Is there a way to mount your Parabellum so there is a gap at the bottom? Having airflow coming up behind the screen really helps limit buffeting caused by negative air pressure behind the screen. Some folks find a Laminar Lip helps, but I don't have firsthand experience.

Hope this helps.
 
#5 ·
I have solved many screen problems using an Aerotrim which is sold online by Heroblobs. Similar to other products but cheaper. Just ordered a dark smoke to go with my Givi screen as I know that it will eliminate buffeting above 60mph, as it did on previous bikes.

I don't know why they are not more popular as they have always worked for me. They work best if you use the supplied hard fitting kit but it means drilling small holes in your screen, if you don't feel confident with the self-adhesive pads you get too.
 
#6 ·
Wow, that is way cheaper than the similar stuff I've seen from MRA and Laminar - I'd love to test those out.

Regarding the OP's screen, can you fiddle with the angle of attack or height? I had to try a bunch of combos with my screen to get it to work fairly well. Boy I miss how well the one on my Vespa worked, that thing blocked it all and wasn't even loud.
 
#8 ·
I have buffeting even looking through the screen as crazy as it sounds. I begin to feel it at around 70. I've used the windshield for about a year now and have made several fairly long trips while staying at about 65mph. The faster I go, the worse the buffeting. At 80, it will rattle your teeth. I had gotten used to it and this thread got me started again. I will experiment some more and will PM you if I find a solution.
 
#9 ·
anytime you start bending the air in front of you, it will create some sort of air turbulence. Air tumbles over the top of the screen which just happens to be around your head level.

Just have to try and smooth out the flow to get rid of it. I've never had a larger screen get smooth flow with no buffeting.
 
#10 · (Edited)
Keep working on trying to adjust the angle of the screen. I have a shorter Givi screen that just bolts on the headlamp, small changes in the angle can have a large effect on turbulence, noise and head buffeting.

My first thoughts when a got the screen was to mount it vertically to get as much deflection as possible but I found the best position for this flyscreen type of shield was sloped back, almost touching the speedo. This gives me clean air around my head and still takes the wind pressure off my chest.

Can you mount the brackets so the support rods from the screen are on back of the handle bar and the shield slopes more towards you?
 
#11 ·
This thread just stopped a few years ago. I'm 5'6" and thinking about getting this screen. It doesn't seem very popular though.
 
#13 ·
Well, I did get the Parabellum Sport shield. I had fooled around with the Rifle Solo (custom size 22"x22") and even added a Laminar Lip to that, but it was very noisy and still shook my Arai helmet.

The Scout looks better and has more radius to it. I got the 22" screen and they do make shorter arms for it, so it is angled back more, about the same as the forks. I'm only 5'6" w/30" inseam. Sigh...that didn't work well either! So I added the MRA X-creen to the top of it, and while it does work a lot better, it's still noisy and I am now forced to look through the deflector! As others have stated, if I lean closer to the screen, it's quiet and smooth. Putting my left hand on my right shoulder also makes things quiet and smooth...blocking the air off of my body from reaching my head.

I made a trip over to the Laminar Lip people and tried one of those, low enough to see over, but it was worse than the X-creen.

This is the problem.....I REALLY think some sort of "lower" is needed to better direct the air coming OVER and AROUND the gas tank!! There HAS to be more to this that a windshield alone just can't fix!

Anybody out there good at making some sort of mock-up for lowers???

Out in here in SoCa, the speed limit on the freeways is mostly 65mph, but "the flow of traffic" is closer to 80mph+ (That's about 130kmh.) Some back roads afford that speed as well, but don't tell anyone.
 
#16 ·
I have had a Givi...two Triumph Roadsters with Cee Bailey replacement shields and currently the Parabellum The best of the bunch was the Cee Bailey on Triumph brackets. I will be returning to this set up if I can't get the Parabellum to work. The Parabellum is an EXPENSIVE NICE LOOKING piece of CRAP IF I had bought this new...I would have returned it Immediately. It is NOT designed for a Triumph Bonneville. It is designed for BMW. It was reworked to fit the Bonneville by the manufacturer. The bottom of the fairing partially obscures the voltage regulator which forces air in weird directions causing a whistle. The windshield angles are ALL wrong...obviously the rake of a BMW is different then a Triumph. I reversed the upper brackets and used the INNER Bolts of the handlebar clamp. To get the correct angle...the mirror staffs have to bent. The fairing now gently rests on staffs. This helps support the fairing...the major cause of the buffeting. I am still working on a more solid mount for the top. The lack of upper support causes this thing to flex and bounce...which in my opinions the cause of the buffeting. I have significantly reduced the whistling , flex and wind buffeting in to the point of tolerable at 70mph...
 
#18 ·
I have found the smaller DART screen the best solution thus far. Or the stock OEM fly screen like they put on the Thruxtons.

You can find those stock OEM ones on E bay to color match your bike. Sometimes you just end up having to wait it out until one show up on there, eventually the proper color will show up. They rotate on and out of E bay almost on a weekly basis these days.
 
#19 ·
The Parabellum Scout fairing/shield will solve many of the problems mentioned. I look over the shield...I chose a height where the "bug-line" starts just above my helmet visor.
 

Attachments

#20 ·
With successive windshields and fairings on a number of different bikes, I have learned that, if you can adjust the angle of the windshield, keep tilting it back, a little at a time, until the buffeting stops. You will need quite a steep angle. This reduces the effective height of the windshield, so the wind will hit more of you, but at least it will be smooth air. Buffeting is unendurable.

On my Bonneville I have a medium-size, handlebar-mounted windshield (Memphis Shades Hellcat) set 42 degrees back from vertical, as measured with the level app on my iPhone. The wind blast hits around the top of my flip-up helmet, but smoothly so, without any snatching. My torso and shoulders are nicely protected so I don't feel as if I am hanging on for dear life. Plus, the windshield looks good, with smooth lines, a gradient black tint and presentable hardware. You can remove or reinstall it in a couple of minutes, but I leave it on.

With something like the Parabellum Scout, maybe you can tilt back the whole fairing or tilt back the windshield
where it attaches to the fairing.

Incidentally, did you know that para bellum comes from the Roman proverb "Si vis pacem, para bellum," which means: If you want peace, prepare for war.
 
#24 · (Edited)
This is a very old thread, I know, but can you tell me how much space you left between the headlight and shield? I have the same Memphis Shades windshield on my T100, and I'm trying to dial in the noise a bit. No helmet shake, but I get a fair bit of wind up from the tank and increased wind noise. I have about 1" between the headlamp and the windshield, and have it angled back about the same angle as the forks. I suspect my screen is more vertical than your 42 degrees from vertical, I think I'm about 38 degrees.

Or, if you could share a picture?
 
#22 ·
This is from an old post in another thread. Full parabellum not sport shield but same concept. Note the blue text, the longer more slanted back windshield directed the airflow better and most importantly was much closer to my helmet, so turbulence at the helmet area was minimized. I assume it just moved the turbulence further back.

I have had a parabellum for 2 years now. I only use it in the winter as here in Texas it gets too hot for summer time. The fairing creates a low pressure area behind it (even with the vent) that pulls up the very hot engine air right in front of you. In less hot climates it probably is not a problem. I got mine used so it is not fitted to me exactly. It really does take all the wind of of you. In my case it did not cause standard buffeting it was more like a vibration. The buffeting was so fast it made everthing slightly blurry but you could not feel you head move like standard buffeting. It was extreamly annoying espically after a long ride. I have heard that most people have no such trouble. I did extensive testing of varying the fairing position and was not able to completly get rid of the "vibration". I then went on to make my own winshield for it which was longer and more angled back. I did lots more testing to get it right but this did fix the problem. It is very nice to ride long distances without getting tired from "fighting the wind".
 
#23 ·
I almost got one of these after reading some glowing owners raves, glad I didn't.
Got a National cycle street shield ex and added an adjustable deflector. Worked quite well, able to adjust the deflector for minimum noise and buffeting, but still noiser than no screen/flyscreen. It improved fuel economy and allowed a higher touring speed but I'm not really a big screen guy.

Removed it and now just use a flyscreen on both my bikes, Just cruise along a bit slower.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top