2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 137Get this manual

2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 137

CARBURATION AND FUEL SYSTEM 500 H.OINTERNATIONAL EMISSIONS SYSTEM Overview International model ATVs are equipped with an
(B) opens and closes based on the vacuum pressure connected to the air ductThe exhaust pipe creates vacuum after each engine
exhaust pulseThe air valve (B) opens and closes based on this engine pulseFresh air then travels through the air injection
tubes (C and D) and into the exhaustThis air (oxygen) enters the exhaust pipe and mixes with the exhaust gases from the engine,
reducing emissionsThe air and exhaust gas mixture then passes through the silencer (E), which contains catalystThis catalyst
also reduces emissions by interacting with the exhaust as it passes through the silencerNOTE: No maintenance or service of