Honda CB 600F Hornet 2007 Shop Manual page 47

GENERAL INFORMATION
EXHAUST EMISSION CONTROL SYSTEM
The exhaust emission control system is composed of a pulse secondary air supply system, a three-way catalytic convert er
and PGM-FI system.
No adjustment should be made for the exhaust emission control system. The exhaust emission control system is separa te
from the crankcase emission control system.
SECONDARY AIR SUPPLY SYSTEM
The pulse secondary air supply system introduces filtered air into the exhaust gases in the exhaust pon. Fresh air is drawn
into the exhaust port by the function of the PAIR control valve.
This charge of fresh air promotes burning of the unburned exhaust gases and changes a considerable amount of hydrocar­
bons and carbon monoxide into relatively harmless carbon dioxide and water vapor.
The reed valve prevents reverse air flow through the system. The PAIR control valve is operated by the solenoid valve. The
solenoid valve is controlled by the PGM-FI unit, and the fresh air passage is opened/closed according the running condi­
tion.
No adjustments to the secondary air supply system should be made, although periodic inspection of the components is
recommended.
PAIR CHECK VALVE
THREE-WAY CATALYTIC CONVERTER
This motorcycle is equipped with a three-way catalytic converter.
The three-way catalytic converter is in the exhaust system. Through chemical reactions, they convert HC, CO and NOx in
the engine's exhaust to carbon dioxide (CO2), nitrogen (N2) and water vapor.
No adjustment to these systems should be made although periodic inspection of the components is recommended.
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PAIR CONTROL SOLENOID VALVE
AIR CLEANER HOUSING
� FRESH AIR
• EXHAUST GAS