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Discussion Starter #1
Help / thoughts. Back to the highly discussed head buffeting. Maryland weather cooperated and I was able to get out for a evening ride, most of it in the evening day light. While riding, I stared playing with the locating the air currents around me again as I've been looking more at windshields and the different styles and heights. One thing I noticed that I had not before is that, though the air on the left side is hitting me on the shoulder, the air on the right is actually hitting the right side of my face. Continuing to move my hand around, I located the source of the air was coming over the top of my stock air filter cover and being directed up my body to my face.

Holding my hand directly between the air filter cover and my face completely stopped the air. Still trying to verity it, I could rest my leg on top of the air filter cover and I had a completely clean air pocket that was much more enjoyable to ride in and what I was hoping for when I bought the Deluxe.

Now, how to fix it? Looking for input. I already have the MS fork deflectors. My first plan is to play with them though it seems it's not their location but that the air is making it around them, hitting the filter cover and deflecting up.

Winter plan is to get Ivan's ECU programming. Hadn't decided about the Power Flo air intake but since it doesn't seem like a windshield issue per say so much anymore, may have to move that air intake up on the list and see if it helps. Has anyone noticed a difference of air flow as a by-product of replacing the air filter box?

Again, thought and opinions are appreciated.
 

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Can't wait to hear real answers from the smart guys on this forum.. Why not a makeshift spoiler on the air box--with some style of course? Kind of like the wing on the back of a dodge Daytona..?
 

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something needs to be separated out here

head buffeting is when the laminar hi speed flow of air coming off the top of the windshield does not make it up and over your helmet before it goes chaotic and turbulent. You cannot see it in air, but in a river its like the smooth flow of water over a large round rock. It stays laminar about halfway across the rock, then it goes turbulent and become white water foam.

If you helmet is touching that white water equal in the air, its like your helmet is in a paint shaker, you eyes are wobbling like jello, you cant read road signs, and your brain is hitting the inside of your skull. That is head buffeting. It normally does not happen below 60...65mph of windspeed.

The fix for head buffeting is almost always to get the air flow off the edge of the windshield thrown up and over your helmet before it collapses into turbulence. Putting fork deflectors on does this by giving the air more of a running start up and over the windshield.

I know there is a lot of discussion about air coming up around the gas tank, but that is not going to cause the air off the top of the windshield to become turbulent. The air you are feeling behind the windshield and around the gas tank and air intake is just a draft. Put your hand over the top of the windshield edge and feel the difference in the wind blast coming across.

I have a Memphis Shades Fats and fork deflectors on my 650. I can ride at 80mph with no buffeting, but its not quiet, and its not a still pocket of air. On a hot sunny day I have to stick my knees out to get some airflow over my chest or Im stewing in my own juices - but again that is just creating a draft across my body, it does not create head buffeting at highway speeds.

If you really want to sit in a still pocket of air at 85mph you need a fully faired motorcycle, like a goldwing or an SVTC, or an FJR1300. Batwings are better than classic police bike style windshields for head buffeting, but there is a reason that Goldwings and SVTCs have full fairings. If that is the kind of ride you want, that is what you need.

you can spend a lot of time and money to make your batwing look like a Goldwing in functionality, and still not be happy with the results. To design this kind of stuff you need a windtunnel.
 

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Discussion Starter #4
KCW, thanks for all the information and feedback.

So, as a correction of classification then for my question, does anyone then have feedback on eliminating the draft that is coming over my air intake which is being directed under my helmet and is causing an undesirable effect at higher speeds? Does anyone have experience or know or have seen if the Powerflo air intake has change the air flow direction? I may try and reach out to Cobra and see if they have input.
 

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looking at your photos something is missing: you!

On my VS650 my right knee is next to the air filter cover. Wondering if maybe its not the air intake that is throwing the air up on the right side, but your lower leg with your knee bumped out a bit by the filter cover?

When I got my windshield and deflectors I spent hours tweaking them in all directions. The best position for the deflectors on my bike is with the front surface matching the angle of the lower part of the windshield. The idea is to make the fork deflectors an extension downward of the windshield, or in your case the batwing.

Its hard to get a 3D perspective from your photos. The deflectors look pretty flat into the wind. Also looks like they would pass the airflow up behind the bat wing, not infront of it where it would continue up over the windshield.
 

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KCW, thanks for all the information and feedback.

So, as a correction of classification then for my question, does anyone then have feedback on eliminating the draft that is coming over my air intake which is being directed under my helmet and is causing an undesirable effect at higher speeds? Does anyone have experience or know or have seen if the Powerflo air intake has change the air flow direction? I may try and reach out to Cobra and see if they have input.
any chance that air is being deflected up over the top of the fork deflector and behind the fairing toward your chest? Raising/lowering the deflector might change the currents noticeably. It looked like the deflector should have removed the intake from the air flow unless your leg is funneling it back in.

Interesting stuff. Can't wait to hear. I'm riding with just the stock windscreen on my 950. There's air coming from all over. I'm fine with it as long as it continues to keep the 80mph air from pushing me off the bike or my head off my neck.
 

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Why not make yourself a set of longer lowers? Making lowers is relatively easy. You can drop the lower edge a good six inches or more quite easily. https://www.instructables.com/id/Motorcycle-Lowers-low-deflectors/

My lowers are home made and I even carved out a curve so it'd clear my air filters as full-turn. The picture is a bit mis-leading as it looks like the air filter curve isn't a smooth curve but it really is. Its a lighting issue that makes it look to be sort of rough.
 

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Discussion Starter #8
I'm going to have to figure out how to do that quote thing... anyway, Greybeard, you may be correct in that my leg is funneling it back in to the air intake cover then up. I do believe it is coming from the cover because I can put my hand right at the edge of the tank directly above the air intake cover and it is gone. I think if the air was hitting me from all over it would be OK but now that it is just hitting me on the right side of my face it's a little a more annoying.

750 Chris, thanks for the link and your example. Never really thought about making my own, that's a good idea.

I'll spend some time Saturday trying to play and adjust them to see if I can clean it up, otherwise it will be off to the hardware store. At least, since I already have the hardware, I'll only need to make the deflectors.
 

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If you do make your own, don't go any thicker than the spoken 0.93" thickness of plastic. That's plenty good enough to handle the air flow, and is easy to work with.
 

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Part of the issue i see is your batwing..the wings are not as prevalent as the memphis. With the memphis you have the option of extensions like a harley on the sides and yours looks like a tsukyayu batwing and is more aero dynamic but causing you wind issues..also your lowers vent up behind the batwing not up in front..this at speed could be causing air fow up the back side of the batwing. 140km and mine is comfy .. wind noise yes but i wear a beany and ear plugs.
 

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if you make your own deflectors use plastic, not sheet metal - safety hazard
 

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Discussion Starter #12
Follow up to this thread I started a couple months back. I followed the suggestion of 750 Chris and followed the link to make my own lowers / fork deflectors. To be totally honest, the change was not as dramatic as I had hoped but do think it helped. As to the suggestion of using the .095 plexi / acrylic, I felt the .095 was way to flimsy and went with the .220, the big box stores carry both, the .220 was more similar to the the thickness of the MS fork deflectors. All in all, it was an interesting project and if worse, it gives me a something else I can work in to a solution for a future problem then it was time and money well spent.

I think they came out real clean and I was able to match the bottom curves of my batwing to give it a more finished look. I pretty much took info from the video to get me started then winged it from there. I made a template out of cardboard, marking the location of the current MS fork brackets, which i re-used. Then, once I picked up the plexi, I cut in in half on the band saw, double face taped the pieces together and attached the template on top of that. I then cut to the template on the band saw and used a hand sander with increasing grit sand paper to take out the blade marks from the edges. I then laid the MS deflectors on the top, marked the holes and just drilled through deflector and plexi. The holes on the MS deflectors are just slightly bigger than 1/2" but 1/2" is fine. I was able to fit the rubber bushings into the holes I just drilled and just re-use the hardware. Pretty easy project all in all.

The MS deflectors do have a slight arc to them so I ended up just flipping my hardware over so my new deflectors would sit where I wanted them to just behind the turn signals.

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Looks nice and very professional. I would suggest tp play with angle of lowers, I'm sure the correct angle is there to achieve the results you want.
 

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Good job i have learned once you get past the fear of working with plexi it isnt that difficult. I made a smoke plexi windshield for my boat and fromed it with a heat gun. Pattern is a must have
 

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Nice work. You may have the beginnings of a cottage industry there.

It's been my experience that most wind buffeting / head-helmet buffeting, whatever you want to call it, is caused by air hitting the rider's legs and getting directed up behind the windshield or faring. This should do the trick nicely.
 

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I just changed over from a 20 year old MS handlebar mounted windshield to the MS Batwing with 9" windshield and added MS Fork Deflectors to my VS 650 Classic. Trying to block more wind (especially on my hands) for winter riding. (I rode to work a couple weeks ago at 6°F for my morning commute!) I've been completely disappointed by how little the Fork Deflectors keep wind/rain/road spray off my legs. Wish I had a bandsaw! I'd try your modification. Nice job!!
 

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I just changed over from a 20 year old MS handlebar mounted windshield to the MS Batwing with 9" windshield and added MS Fork Deflectors to my VS 650 Classic. Trying to block more wind (especially on my hands) for winter riding. (I rode to work a couple weeks ago at 6°F for my morning commute!) I've been completely disappointed by how little the Fork Deflectors keep wind/rain/road spray off my legs. Wish I had a bandsaw! I'd try your modification. Nice job!!
You can use a jig saw just make sure you put some tape down so the bottom doesn't scratch the plexi.
 

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I also made some lower fork deflectors to cure the same problem as the OP.
On the 650 classic, the wind was hitting the air cleaner then up over my knee to buffet my helmet .
A tip. Make some of different sizes and shapes from cardboard, tape them on and go for a ride to see what works best!
Cardboard is a lot cheaper and easier to work with than plex. Plus you can say you used CAD = cardboard aided design.
 

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Discussion Starter #20
Thanks all. I am pretty happy with the look and function. JimCanaday, the band saw did make it a little easier, the edges were still pretty rough so it took going through a few different grits of sand paper on a sanding block and cordless sander to get a nice edge. You can see in the instruction link above though from 750 Chris that the person who made the instructions just used a jigsaw.

last quick note, I'd suggest having another small piece of plexi below the two when you drill through them and have them down tight. I had them on a block of wood, still with the protective film and tape on them and the back side of both holes on the bottom piece came out a little rough and had to be sanded. I presumed it was from going through the plexi to the wood and the bit biting a little different. Good luck
 
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