Honda TRX400EX FOURTRAX 1999, Service Manual

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GENERAL INFORMATION
EMISSION CONTROL SYSTEMS
The California Air Resources Board requires manufacturers to certify that their comply with applicable exhaust
emissions standards during their useful life, when operated and maintained according to the instructions provided.
SOURCE OF EMISSIONS
The combustion process produces carbon monoxide and hydrocarbons. Controlling hydrocarbon emissions is very important
because, under certain conditions, they react to form photochemical smog when subjected to sunlight. Carbon monoxide
does not react in the same way, but it is toxic.
Honda Motor Co., Ltd. utilizes lean carburetor settings as well as other systems, to reduce carbon monoxide and hydrocar-
bons.
EXHAUST EMISSION CONTROL SYSTEM
The exhaust emission control system is composed of
a lean carburetor setting, and no adjustments should be made except
idle speed adjustment with the throttle stop screw. The exhaust emission control system is separate from the crankcase emis-
sion control system.
CRANKCASE EMISSION CONTROL SYSTEM
The engine is equipped with
a closed crankcase system to prevent discharging crankcase emissions into the atmosphere.
Blow-by gas is returned to the combustion chamber through the air cleaner and carburetor.
AIR CLEANER CONNECTING TUBE
CARBURETOR
CRANKCASE BREATHER STORAGE
FRESH AIR
BLOW-BY GAS
TANK
NOISE EMISSION CONTROL SYSTEM
TAMPERING WITH THE NOISE CONTROL SYSTEM IS US. federal law prohibits, or Canadian provincial laws
prohibit the following acts or the causing thereof: The removal or rendering inoperative by any person, other than for pur-
poses of maintenance, repair or replacement, of any device or element of design incorporated into any new vehicle for the
purpose of noise control prior to its sale or delivery to the ultimate purchaser or while it is in use; the use of the vehicle
after such device or element of design has been removed or rendered inoperative by any person.
AMONG THOSE ACTS PRESUMED TO CONSTITUTE TAMPERING ARE THE ACTS LISTED BELOW
1.
Removal of or puncturing of the muffler, baffles, header pipes or any other component which conducts exhaust gases.
2. Removal of, or puncturing of any part of the intake system.
3.
Lack of proper maintenance.
4.
Replacing any moving parts of the vehicle, or parts of the exhaust or intake system, with parts other than those specified
by the manufacturer.
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