20. EXHAUST EMISSION CONTROL SYSTEM PEOPLE/PEOPLE S 250 SCHEMATIC DRAWING Carburetor Air Injection Vacuum Cut-off Valve Reed Valve Secondary Secondary Air Air Cleaner Cleaner Into Hole EXHAUST EMISSION CONTROL SYSTEM The exhaust emission control system adopted in this model utilizes the reed valve to draw secondary air into the exhaust system for re-combustion by means of exhaust pulsation so as to minimize the exhaust emission. FUNCTION Item Purpose Function It filters the fresh air drawn for re-burning to prevent Secondary Air Filter secondary air. dirt or dust from affecting the operation of the air Cleaner injection cut-off valve. The air injection cut-off valve usually opens to lead air into the exhaust muffler in which air is re-burned Prevent exhaust Air Injection Cut- to reduce CO. When the throttle valve closes muffler noise and off Valve suddenly, the air injection cut-off valve is actuated backfiring at sudden by vacuum to close and cut off secondary air in deceleration. order to prevent exhaust muffler backfiring due to air in the exhaust system. When the motorcycle speed is less than 50km per Control the secondary Reed Valve hour, the reed valve operates to draw secondary air air inlet to reduce CO. into the exhaust system for re-combustion. 20-1