windshield blather

[DimitriT]

So after riding in the cold all winter (yea, I'm a pppsssyyycchho) I finally decided (now that winter just about over) to get myself a new, bigger windshield. I started with this unit. I mounted high up and at an angle and it gave pretty good protection around the chest and neck area, although the face, hands and arms had no protection. The new shield was this unit. It looked nice on the bike and I was pleased with the construction and installation. But, 2 minutes on the road and I hated it. The problem was that there was alot of turbulance off the top edge which hit square on the helmet. The noice was unbearable. Visibility was also much worse. There was also an area on my upper back which started to feel the wind as it curled around me. Now I'm no expert on aerodynamics (but I do understand some basic stuff) and here's my theory as to why the small shield worked so well: air flowing over the small shield was able to get around the bottom as well as over the top surfaces (since the shield is mounted at an angle). The result is an airfoil which deflects the air without causing a separation bubble behind the shield. The larger shield did not allow air under it (as it somewhat sealed itself around the headlamp). The result is a big region of low pressure which cause the air to swirl around, creating the buffetting.

[ruddy]

I have both of those shields myself. I've been using the Plexifairing 3 for many, many years, and I got the Deflector shield for warm weather riding a couple of years ago. In my experience, the way to deal with the problems you're having is to tilt the top of the shield more to the rear. I actually tilt them both about the same amount. If you line up the lowers so they're parallel to your fork tubes, you should be OK.

[ruddy]

By the way, your complaint about visibility makes me think you're looking through the windshield. The top portion does have quite a bit of distortion, but you're suppose to be looking over the top of the shield. Tilting it more should help that, too. If it's still too tall after readjusting, a belt sander will trim it in short order.

[ccratin]

Ruddy, glad to hear of someone who has one. Is it the plexifairing? I have the deflector shield on my 1100. It worked great on my 450, but it really looks out of place on mine. Plus, I do ride in the winter all the way through and I'd like to have a little more coverage for the cold. In the summer, I generally don't use one.

[wharrah]

I use one like DimitriT's second one... I love it, actually. Maybe he's more of a 'conneseur' than I am, but I don't have problems with noise or odd wind buffeting... But, maybe its my height being different than his or something, but I also do have it aligned so it basically follows the same angle as the fork tubes... Might have something to do with it.

I definitely can look OVER the top of it, though. To each his own, I guess.

[ruddy]

Hi ccratin, Yes I have the Plexifairing 3, which has the lowers. I used to ride all year (except during snowstorms) in Denver rain or shine, and that full coverage windshield made it possible to do so. I don't ride much during the winter here in Spokane, however, because the climate is damp and causes too much black ice in the mornings. The quick detach feature allows me to remove or mount it in two or three minutes w/o tools, which is really nice. The Deflector Shield I got for long runs in warmer weather uses the same mounts, so I can switch between full coverage to partial to none in a matter of minutes. :-D

[Roadwarrior]

I have the Plexistar 2 on my bike. I had a lot of wind noise at freeway speeds, so now I wear earplugs and my problem is solved. I am willing to use earplugs because the comfort level with the Plexistar is so much better.