Perhaps because of this??? "mufflers that use an “excessive or unusual level of noise” and mandates that mufflers must be identical to their factory setting, comparable to factory equipment, approved by the Superintendent, or meets or exceeds standards of SAE International, ANSI, or the U.S. Department of Transportation".

Now I support stifling the obnoxiously loud open exhaust, as others have written, on some of these motorcycles and ricers. They are beyond some aftermarket mods for performance and better sound, and have reached pure torture to the ears on some and pure obnoxiousness. But a tuned exhaust on an old 70's car will not be allowed under this Bill.