Honda NSA700A DN-1 2009, Service Manual

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GENERAL INFORMATION
and PGM-FI system.
No adjustment should be made about the exhaust emission control systems. The exhaust emission control system is
separate from the crank case emission control system.
SECONDARY AIR SUPPLY SYSTEM
The pulse secondary air supply system introduces filtered air into the exhaust gases in the exhaust port. Fresh air is drawn
into the exhaust port by the function of the PAIR (Pulse Secondary A ir Injection) control valve.
This charge of fresh air promotes burning of the unburned exhaust gases and changes a considerable amount of
hydrocarbons 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 Engine Control Module (ECM), and the fresh air passage is opened/closed according the
running condition (ECT/IAT/TP/MAP sensor and engine revolution).
No adjustments to the secondary air supply system should be made, although periodic inspection of the components is
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 (CO
2
), dinitrogen (N
2
) and water vapor.
No adjustment to these systems should be made although periodic inspection of the components is recommended.
recommended.
AIR CLEANER HOUSING
] FRESH AIR
EXHAUST GAS
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