Odd question, but what type of helmet are you using, and have you tried any others?

 

Full face, Scorpion. I've thought about it, but I'm trying to solve it at the source so I'm not limited on helmets going forward.

3/4 or half helmets just aren't an option. I'd have to find a shop that would let me test ride a bucket before buying.

 

I’m with you on the FF helmet.
I’ve got no answers, but I am curious about how you solve it.

 

May also want to try a different kind of earplug. I have a set that touches the foam inside my helmet and it can cause some resonance. When the ear plugs touch the inside of the helmet it seems the noise is transmitted from the helmet through the ear plugs into my ear, very annoying.

I have been using these with great success.

 

I've got an 07' RoadKing and there is no way on mine to adjust the shield.

 

What you’re describing is called buffeting.
I’ve fought this problem on every bike with a windshield I’ve ever ridden when wearing a helmet and have been able to pretty much eliminate it on my 08 RK with the following…

1. Front fangs
2. Aftermarket windshield with a vent. It’s tall enough so that I can just see over it on a flat road. I can’t recall the brand but it also has a lip on the edge. The vent really helps to equalize the pressure between the front and backside of the shield.
3. A low profile helmet. I’m using a 3/4 Daytona.

 

Going back 10+ years ago, I purchased a Shoei full face helmet that was horrible behind the windshield on my MotoGuzzi. After research, I found that it was designed for sport bikes, and as such was designed to work best with a forward lean position. I sold that helmet and bout another Shoei that was designed for cruisers. I've forgotten the model numbers.

 

Not buffeting in this case but thanks for the tips. Anything less than full face helmet is out of the question. I'm at ATTGATT nerd. Weird in the HD crowd in my area but I is what I is.

• It happens with, OR without a windshield. I run the 21" big one; I had a shorter one but the buffeting on it was awful. Very distinctly different symptom
• I do have the fork deflectors (fangs) - that did solve what buffeting issues I had.
• It happens at low speeds as well as high. Any time the engine is in that 1900-2800 rpm range.
  • 20 MPH speed limits are BRUTAL because both 1st and second gear sit RIGHT in that RPM range at low speeds like that.
• When I remove my earplugs inside the helmet the resonance goes away, but wind noise is rough (for me) above 40 mph. Let alone an extended freeway trip
• If I keep my head in the same position, but just roll my hips back slightly (to get my tailbone off the seat pan) the resonance is greatly reduced to completely eliminated. But that's a very awkward posture to keep for more than a minute or so.

 

I might have to try those. My normal go-to earplug is the orange foam one (Howard Leight brand), rated at 32db attenuation. Been fine on every other bike I've owned since I started riding but different ear pro is cheap to try.
I did try a "hi-fidelity" filter-style silicone set but really were not any better.

 

Mods are done:
Wide bicycle gel seat cover between the pan and the original foam
2" green upholstery foam added on top, cut to match the shape (more or less). Added maybe 3/4" seated height.
​​​​​​Results: might have actually made my issue worse. Sits pretty comfy but didn't solve my resonance problem.

I bought a slightly different earplug that I'll try next. I also plan on going back to the independent shop I bought at and see if they'll let me borrow the one-piece seat that was on it for my test ride briefly since I don't remember this symptom from then.

ETA: They had a different seat on it before I bought it, but it was slick enough I felt like I would slide backwards when giving it any real throttle. They were nice enough to trade me even for the OEM style seat I have now. If the slick banana seat fixes the resonance then I'll just deal with the slickness separately.