RSA 266:59-a Motorcycle Noise Levels.
Title: XXI - MOTOR VEHICLES
Chapter: 266 - EQUIPMENT OF VEHICLES
I. No person shall operate in this state any motorcycle which produces a sound level in excess of the following decibels, when measured in accordance with the provisions of the SAE International Recommended Practice SAE J2825, "Measurement of Exhaust Sound Pressure Levels of Stationary On-Highway Motorcycles":
(a) For all motorcycles, 92 decibels while the engine is operating at idle speed; or
(b) For motorcycles with less than 3 or more than 4 cylinders, 96 decibels while the engine is operating at 2,000 revolutions per minute or 75 percent of maximum engine speed, whichever is less; or
(c) For 3 and 4 cylinder motorcycles, 100 decibels while the engine is operating at 5,000 revolutions per minute or 75 percent of maximum engine speed, whichever is less.
II.