Ive never seen them bust out a sound meter, but have been ticketed twice.
“All modified exhausts are illegal period.” TOC Officer of the Law
If they are gonna get you - there’s not much fighting back unless you are 100% not at fault.
Maybe bike regulations are different, but seeing as they prob. ticket a ratio of (1 : 247,094) being (Harley : Streetbike) Im assuming its up the the cop