CF MOTO CF125T-19 2003, Service Manual

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1 Overhaul Information
1
Secondary air inlet supplying device
Secondary air inlet supplying device sends the fresh air from the secondary air filter to the exhaust pipe,
where the not-fully-combusted mixed-gas in the exhaust gas can continue to burn. In this way the main
contents of HC
¡¢ CO and NO
x
of the exhaust gas will be turned into harmless carbon dioxide and water.
To keep the exhaust gas in the exhaust pipe from flowing backwards, a one-way tongue valve is set in the
Secondary air inlet gateway (inner cylinder head cover).
The switch of Secondary air inlet gateway is controlled by Secondary air inlet control valve; The pin valve
on/off is controlled by the diaphragm through the engine suction vacuum.
Though this system does not need regular check, it is very important to do maintenance of the internal parts
periodically (once in one year).