Emission Standards Reference Guide
Highway Motorcycles -- Exhaust Emission Standards
| Year | Class | Engine Size (cc) |
HC (g/km) |
HC + NOx (g/km) |
CO (g/km) |
Useful Lifea | Warrantya | |
|---|---|---|---|---|---|---|---|---|
| Federal | 1978-2005 | I | 50-169 | 5.0 | - | 12.0 | 5 / 12,000 | 5 / 12,000 |
| II | 170-279 | - | 5 / 18,000 | 5 / 18,000 | ||||
| III | 280+ | - | 5 / 30,000 | 5 / 30,000 | ||||
| 2006+ | I-Ab | < 50 | - | - | - | 5 / 6,000 | 5 / 6,000 | |
| I-Bb | 50-169 | 1.0 | 1.4c | 12.0 | 5 / 12,000 | 5 / 12,000 | ||
| II | 170-279 | 1.0 | 1.4c | 12.0 | 5 / 18,000 | 5 / 18,000 | ||
| 2006-2009 | III (Tier 1) |
280+ | - | 1.4 | 12.0 | 5 / 30,000 | 5 / 30,000 | |
| 2010+ | III (Tier 2) |
280+ | - | 0.8 | 12.0 | 5 / 30,000 | 5 / 30,000 |
Notes:
General applicability: These standards apply to 1978 and later model year, new gasoline-fueled motorcycles built after December 31, 1977, and to 1990 and later model year, new, methanol-fueled motorcycles built after December 31, 1989, and to 1997 and later model year, new, natural gas-fueled and liquefied petroleum gas-fueled motorcycles built after December 31, 1996, and to 2006 and later model year new motorcycles regardless of fuel.
a Useful life and warranty period are expressed in years and kilometers, whichever comes first.
b Starting with the 2006 model year EPA re-defined Class I to include motorcycles with engines smaller than 50 cubic centimeters. These new previously unregulated vehicles are Class I-A, and the pre-existing Class I became Class I-B.
c This is an optional standard that allows manufacturers to average their emissions or transfer emission credits across classes.
Code of Federal Regulations (CFR) Citations:
- 40 CFR 86 Subpart F = Motorcycle emission test procedures
- 40 CFR 86.410-90 = Emission standards for MY 1990-2005
- 40 CFR 86.410-2006 = Emission standards for MY 2006+