Topic: Windshields

[jakec]

I got this small windshield to try out, the common spitfire one. I just mounted it this afternoon and went for a ride. What I found was that it almost felt like the wind on my head was worse? While there was almost no wind on my body which is nice. But now I'm sitting at home and I feel kind of dizzy like my head was getting knocked around. I rode about 30 miles vary speed 60-85mph to try and feel things out.

I mounted it so that the bottom rests on the headlight bucket, and the angle of the shield was about parallel to the rake. I'm 6'-2" so I expected my head to go above the coverage of the shield. However I'm wondering if the shield is making some kind of current to make it worse based on my height.

While I was going about 80 I moved my head up and down. Up was more buffeting. As I moved my head down, it got less and less, with a point where the wind was really loud but little buffeting (I assumed this was like the "slipstream" of the shield or something). Then if I got my head way down then there was no wind at all of course.

I'm just wondering if i can adjust the shield somehow or maybe if this is just in my head?

[Kevin]

I've seen little shield extenders that have a lip to change the jet stream. Honda had a factory shield that was motorized to extend the height. I forget the model though...


Sent from my SM-N960F using Tapatalk

[Alan F.]

It's not in your head at all. Try raising the screen a little and steepening the angle. This is why frame mount fairings worked so well, they were out in the wind forward of where any handlebar mounted windshield would be.

[andy750]

I am 6`4 and this windscreen on my CB750 is fine (no buffeting) but it has to be just at the right angle for it to work. On my VStrom I have a windshield lip mounted that helps a lot!

[70CB750]

You have to work with it.   Not every shield works on every bike. I put the one from Dorothy on the CB900C and the wind pounded the #$%* out of my head too.

[ekpent]

  This nice original owner F0 that I bought came with a windshield and I tried riding with it. It was horrible. I'm 6'3" and it created a ton of turbulence and noise around my head and faceshield and some other odd effects on my chest. It also really spoiled the handling. Being handlebar mounted it made the front end twitchy and unsettled. Took it off and the grin reappeared. One also came with a Suzuki GSX1100G I bought and it was a ton better with it off.

[70CB750]

  This nice original owner F0 that I bought came with a windshield and I tried riding with it. It was horrible. I'm 6'3" and it created a ton of turbulence and noise around my head and faceshield and some other odd effects on my chest. It also really spoiled the handling. Being handlebar mounted it made the front end twitchy and unsettled. Took it off and the grin reappeared. One also came with a Suzuki GSX1100G I bought and it was a ton better with it off.

I have experience only with one original factory option, but it was amazing.  At 100mph you barely noticed the wind.   

[jakec]

Mine is pretty much mounted just like this. I think I will try and raise the shield a bit if I can. I have a big trip this weekend so I'll bring the tools and see if I can dial it in more or maybe take it off if I have to.



To describe the feeling more, it was like the wind buffeting was reduced, but instead there was more frequent, smaller buffeting hitting my head. As opposed to the usual really strong buffeting.

Usually when i ride over 75mph my neck gets tired and my arms get tired from holding on for dear life. With the shield there was none of that, but I just felt dizzy from my head being "vibrated" I guess.

[70CB750]

You experienced vortex shedding:

https://en.wikipedia.org/wiki/Vortex_shedding

Basically on the edge a vortex is created and at certain point it breaks loose and flies down the stream  - hitting your head  - and it keeps recurring.
Frequency of that is described bu Strouhal number:

https://en.wikipedia.org/wiki/Strouhal_number


I am sure it makes you feel  so much better about your problem here 

[jakec]

People said above that a windjammer works better, is that just be cause it's bigger? Because I would think being farther away would be worse. Or am I just in the worst possible spot, where the shedding is worst? (Shown in .gif on wikipedia)

If i'm understanding correctly then the best place to be is by the check mark, what's the worst place? right as the shedding begins? I can't move the shield any further forward but I may be able to bring it back and up.

[jakec]

I have changed the position so that the shield starts at the chrome ring around the gauges. so it's about 4" higher with the same rake. Also about 3" further back. Hopefully that makes it better.

[andy750]

For me it was all about the angle...just have to test ride it to see what works best for you.
Good luck!
Andy

[Kevin]

My first long trip was from Seattle to Sipapu NM on my Suzuki Intruder VS1400. 4000 miles round trip without a windscreen.
Did a similar trip the following year, but this time with a windscreen that my brother surprised me with a day before we left.
It made a huge difference!
That was 18 years ago, I still have the Intruder and the windscreen :-)

Sent from my SM-N960F using Tapatalk

[70CB750]

People said above that a windjammer works better, is that just be cause it's bigger? Because I would think being farther away would be worse. Or am I just in the worst possible spot, where the shedding is worst? (Shown in .gif on wikipedia)

If i'm understanding correctly then the best place to be is by the check mark, what's the worst place? right as the shedding begins? I can't move the shield any further forward but I may be able to bring it back and up.

Unfortunately havng your head at the edge of the windshield is not possible, i would change the angle as Andy said.   Factory windshields often have the top rim bent up to send those vortexes over your head. 

Sorry, man, i had college classes on this 30+ years ago, dont know more than i already posted.

[Bankerdanny]

I used a similar windshield on two different 550's on long trips. A 1400 mile trip on my '77 K in 2011 and 4700 miles on my 75F in 2017.

For my 1200 miler on my '76 750F last year I used a smaller cafe-ish style.

I'm about 6-4 and they all worked well. I was amazed at how the smaller one worked last year. It didn't get my head out of the air like the Vetter on my GoldWing did, but it kept the wind off my chest and made long stretches at 70-75mph perfectly comfortable.

[jakec]

Well it was definitely making it worse, I stood up on the ride and the difference was great. So I ended up just adjusting it to point down so the bad air was hitting my chest (which I can't even feel). Not sure what I will do with it now.

[HondaMan]

I can speak to the Windjammer question, been riding behind mine since 1972 February when I rode it home in the snow and below-20 degree temp: it was an 80 mile trip for the first time with a 'windshield' and the very LAST time I toured without a Vetter.

Several things are involved, one of which is the vertical angle: look at pix of the Vetter and the Goldwing fairings and you will see what I mean. The more rakish angle of these systems push the air up over your head (and sideways away from your body as well) and slip through the turbulence: it starts working at 40 MPH and by 100 MPH, if you ride behind someone in front of you also with a Vetter, falls back on the 'pocket' at that point. I used to beat my brother up on his 500 (with a Vetter) when we'd be out sparring with each other: I'd get in front of him at about 90, pull around him and get about 10 feet in front, which would rattle him but good!

My wife also attests that between 45 and 55 the backseat ride changes from buffeting winds to a quiet, still pocket. She usually sits back there with a paperback book pressed up against my back, reading while we cross places like...Kansas....

[70CB750]

Well it was definitely making it worse, I stood up on the ride and the difference was great. So I ended up just adjusting it to point down so the bad air was hitting my chest (which I can't even feel). Not sure what I will do with it now.

You can see in Reply #4 where I pointed my windshield.