1997-2001 Honda TRX250 Fourtrax Recon Service Manual, Page 28Get this manual
GENERAL INFORMATION
EMISSION CONTROL SYSTEMS
The Californ ia Air Resources Board (CAR B) requires manufacturers to certify that heir ATVs comply with applicable exhaust emissions standards dur ing their useful life, when operated and maintained according to the instructions provided (Cal ifornia type only)
SOURCE OF EMISSIONS
The combustion process produces carbon monoxide and hydrocarbonsControl of hydrocarbons is very important because, under certain conditions, they react to form photochemica smog hen subjected to sunlig htCa rbon monox ide does not react in the same way, but it is toxicHonda Motor Co Ltdutilizes lean carburetor settings as we ll as other systems, to reduce carbon monoxide and hydrocarbons