stock windshield modification

vic ray · Oct 21, 2005

I have looked at several of the threads on this sight and others concerning aftermarket windshields. I read a few that recomended the california scientific shield. They claim their shield eliminates the back pressure that the stock shield puts on your helmet. I noticed they have a couple of vent slots cut out of their shield near the w bracket that it attaches to. They say the cut outs eliminate the back pressure. I allready have their micro edging on my shield and am fairly pleased with the results. It virtually eliminated the buffeting but I still get the back pressure. I like the way the stock shield looks on the bike and would really like to keep it on it.

Has anyone tried to cut a couple of vent holes on their stock shield like the california scientific one. and if you have, what were the results? I am probably going to try it on mine. I even thought of maby drilling several 1/4 " holes in a pattern similar to the size of the cut outs on the california screen. Maby even countersinking or beveling where the holes face out. I think if it elliminates back pressure with their shield it should do the same for the stock shield.

Thanks in advance for your help.

Vic Ray.

JimLor · Oct 21, 2005

Vic - talked with an aeronautical engineer the other day. He says what you want to do is break up the air so that it comes together farther back (behind you) and won't push/pull/bobble you. He seems to think the edging is a pretty good way to go. I'll talk to him about the holes in the screen and get back to you. Heck, maybe we can benefit from our tax dollars (he's a govt guy).

Jim

TWILKIN650 · Oct 21, 2005

As I suggested in an earlier iteration of this thread......I wonder if someone with a stock shield and a CalSci shield with the cutouts would duplicate the exact cutout pattern on the CalSci shield, cut the stock shield to match, install, and report back on any improvements the cutouts make. It would be a service to our community if it turned out to be a simple improvement that could be applied to those with stock shields. Zero dollars is always a quick payback.

Maybe it isn't the complete answer, but........I had an AeroFlow fairing on a K100RS with similar NACA vents cut at about the same place and it was a wonderful shield. The other main advantage was that it fit over the stock shield and was removable via industrial duty Velcro dots on stock fairing and shield in about 10 seconds in hot weather or if you wanted to wash the bike. No buffeting, great protection, great bang for your buck. Wish AeroFlow would do the same for the FJR. I'd buy one in a NY minute!

leebunyard · Oct 21, 2005

I've thought very seriously about doing the vent cutout thing on the Cee Bailey +4/+4 standard contour windshield on my '04 FJR. It would be easy to do, just drill four holes in a rectangular pattern and cut the vent out with a sabre saw or hacksaw. I've been thinking about doing this ever since I bought a new windshield for my '87 GL1200 GW this past Spring. I bought a Cee Bailey windshield for the GW that came with a cutout vent in the lower center portion of the windshield. I could not believe how much of an improvement that windshield is over the stock windshield with no vent that it replaced. It cut the wind noise and buffeting TREMENDOUSLY and made riding the GW much more enjoyable. I love it.

When I get some time, I think I will try to duplicate it on the FJR windshield. I don't know of any reason it shouldn't work as well on the FJR as it does on the GW.

Lee in the Mountains of Northern California B)

FastJoyRide · Oct 21, 2005

I will be eagerly awaiting your report!

vic ray · Oct 21, 2005

O.K. Guys and Gals,

It's going to rain this weekend and I can't think of any thing better to do that to try my theory on the stock screen with the cutouts. I hope it works. I will try to give a full report as soon as I have time to test it out. I could probably even post a couple of photos with the help of a member or two. You never know until you try so I guess I will be the guinie pig.

Vic.

vic ray · Nov 1, 2005

Well I did it! I cut two slots out at the bottom of the stock windshield like the California scientific screen. I didn't have any dimensions to go by but I tried to keep it as close to the photos I have seen. I have had two weeks of riding to evaluate the results and what I have found is doing this eliminates some existing problems but creates a few new ones.

The pressure on the back on my helmet was greatly reduced but still exists a little which is what I was hoping to eliminate. One big draw back is the amount of wind you feel on your face with the screen in the full up position and a constant buffeting. Before the cutouts I felt pretty well protected from the wind in my face but with the cutouts there is a constant flow of air to your face. So, I didn't get the results I was hoping for. I desire a screen that could get the wind blast off of you and not put a constant downward force on the back of my helmet. Please someone tell me does this screen exist? I have been looking at the rifle screen and tuning block. Can anyone give me a recomendation?

As for now I would say leave the stock screen as it is. It isn't worth the trouble.

Vic.

FJRocket · Nov 1, 2005

An easier way to help eliminate the back pressure would be to "tune" a shield. I've noticed that since I tipped my CB+4+4 back by adding nuts and washers where the W frame is attached to the motor arms really opened up the bottom of the shield. There is a substantial gap at the bottom now, and a lot of air comes through (or it helps break it up, whatever). It does seem like it really does have a lot less pressure because of the change. So you might want to just "tune" your shield before you start cutting on it. Perhaps you'd get the same effect. YMMV...

Freesundae · Nov 1, 2005

What size nuts are they, I would like to pick some up on my way home...Does anybody know?

Tim

paint · Nov 1, 2005

I used stacked washers (10mm) on my '03 to do the same thing. DO NOT do it without using 10mm longer screws.

Don't ask how I know.

nusman68 · Nov 1, 2005

I have also been considering similar 'windshield surgery' due to buffeting, etc. Recently I bought one the 'Rumblestrip' self adhesive rubber strips that sticks across the top/rear portion of your helmet, to see if it would help; it did. It made a noticeable reduction in buffeting on my HJC. Definitely worth the $15.00 as far as I'm concerned. I'm sure I'll still do the other, but this did give some needed relief.

FJRocket · Nov 1, 2005

What size nuts are they, I would like to pick some up on my way home...Does anybody know?
Tim

Tuned windshield thread

I used M6 countersunk screws. Paint is right, you have to get longer screws, the two BIG ones that hold the W frame to the motor arms. I used stainless nuts that fit the M6 screws, but you could easily use spacers or washers, like Paint and others have stated. I was able to get the replacement screws at my local True Value. Took the OEM screw in and matched it. I think 10mm longer is the MAX your going to open it.

This does tip the top of the shield back and down at you, so it will sit lower when all the way down. Also, beware that the motor arms MIGHT hit the tupperware at the end of the travel slots in your fairing. Especially in the cold weather, this could easily crack that baby. Some have used a dremel to open up the slots. I just try to be careful. I rarely use it in the full upright position anyway.

Penforhire · Nov 1, 2005

I recently pulled my old Laminar Lip off my OEM screen to my +3+4 CB flip screen. I could not place it at the top (as LL recommends) so it is maybe four inches down from the top, well out of my view. Funny thing is it made a big difference in noise, turbulence, and back pressure. I'd say it cut everything in half when the screen is full-up. I can ride at highway speed without earplugs (probably still too loud but my ears don't bleed anymore).

I know, take pics. If I ever do I'll post 'em.

stock windshield modification

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