I should have noted at the beginning that my contact with the police is what sparked my original post about the motorcycles. I called Zone 5 and asked what specifically can be done and was told verbatim, "There is nothing illegal about them," and he went further to say that the city noise ordinance does not cover motorcycles, just music levels coming from vehicles. That is true. Here is the city code: https://www.city.pittsburgh.pa.us/pers-depo/Exam/TITLE6.PDF

Does the state code override/add to the city code? 

Sorry if I'm making a bigger deal of this than it deserves. Let's take any further discussion of this off the list to keep from annoying people who sleep just fine. :)  

On Sun, May 27, 2012 at 5:42 PM, Guru <chefguru1@yahoo.com> wrote:
The City's noise ordinance makes a specific distinction for noise related to/from vehicles.  http://www.pacode.com/secure/data/067/chapter157/s157.11.html

The PA Code already specifies decibel levels for motorcycles, which happens to be lower than what is required for other vehicles.

As a motorcycle rider, let me assure you that there are a number of motorcycle rider associations with nation-wide memberships and multiple local chapters around the Pittsburgh area (not biker gangs, but biker education and advocacy groups) that have powerful lawyers on retainer that regularly go to bat to defend motorcycle rights across the country.

I'm not trying to rain on your parade, but if you think a few letters from some of the neighbors will make a difference, you should be aware that this will be met by opposition from a number of motorcycle advocacy groups that already have connection at the State and National level.

Are you certain that none of these "ridiculously loud motorcycles flying through the neighborhood" aren't actually some of the neighbors that you might be able to talk to about this issue?  I've seen a few bikes parked in front of houses in the neighborhood, and it's possible that maybe some of these inconsiderate people [sic] are just your neighbors who might not own a car who work a late shift and are returning home?  I've got a Harley that makes a lot of noise as well, but when I'm coming home at 3 or 4 am, I know how to ride the bike so it's not as loud.

My advice, considering there is already a law in place dealing with this, is to contact the police, and if this is happening regularly at certain times, see if you can get someone out there to check it out, have them bring a decibel meter and check.  If the person(s) riding the motorcycle really have pipes that are louder than what it legal, let the cops deal with it.  Otherwise, if it turns out that the motorcycle is actually within the legal limits, but it just seems so much worse because it's night time, and there is very little other noise, then there isn't really much you can do besides just dealing with it.

Have you contacted the police about it?