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Thank you Mr. Helper.

Kevin Q,
Thanks for your reply. This is what Harley=Davidson says:
"Straight off the line today, Harley exhaust systems can emit noise as high as 80 decibels (dBs), give or take depending on the model." That's 25 decibels above the limit of 55 decibles. If you remember your High School math, decibels are calculated with a logarithmic function. So 25 decibels equates to over 17 times the allowed limit on a linear scale. Are you sure your sound meter is calibrated correctly? Thanks for having this discussion and thank you for your service to our great nation. Pete

Sir, I believe we should discuss your misinterpretation of the health and safety aspect of motorcycle exhaust noises. Being that every 3 decibels of increase translates to a perceived doubling of the intensity of sound, I agree that this is an important topic and am happy to clarify further. 55 decibels ABOVE ambient is an important distinction but then so is a phrase you missed that is “unprotected.” According to the Academy of Sound Science, sound protection refers to “any sound filtering device that lowers the perceived decibel level at the source or receiver.” Luckily for you, your walls would count. When we ride by if you simply go inside your home, then you will be protected. There, problem solved. All you have to do is go inside and everything is fine. Thank you to the fine scientists at A.S.S. for their hard work and study of this topic.

Dear Sir;
Per your own post the noise limit is 55 decibels ABOVE AMBIENT NOISE LEVELS. Therefore you must first recognize what “Ambient Noise Level” is. On average in a Metro are like Arlington or D.C. metro ambient noise level is approximately 60-70 decibels. Therefore 55 above that would then translate to 115-125 decibels. With a stock Harley Exhaust being 80 decibels on average even a modified exhaust would be under the 115 decibels you say are the limit.
So while I appreciate your circumstance and your suffering we do remain within the limits.
I recommend that you consider downloading an app that displays the decibels using your phones microphone. There are several free apps. This way you can record ambient noise levels at different times of the day, and it will be handy next year to check our levels as we process out.

An electric toothbrush is 55 decibels...