Honda CB900F Service Manual page 39

GENERAL INFORMATION
EMISSION CONTROL SYSTEMS
SOURCE OF EMISSIONS
The combustion process produces carbon monoxide and hydrocarbons. Control of hydrocarbons 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 injection settings as well as other systems, to reduce carbon monoxide and hydrocarbons.
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 throttle body.
THROTILE BODY
AIR CLEANER HOUSING
~
FRESHAIR
. . BLOW-BY GAS
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