A new California law requires street motorcycles registered in the state and built on or after Jan. 1, 2013, to have an exhaust system label certifying the motorcycles meet federal sound limits...
...the new law now makes it a state crime to operate any motorcycle registered in the state that was built on or after Jan. 1, 2013, that doesn't have a federal Environmental Protection Agency exhaust system sound emissions label.
...in addition, the law requires aftermarket exhaust systems made on or after Jan. 1, 2013, to display the EPA sound emissions label...