2008 Polaris ATV Sportsman 300 400 H.O. Service Manual, Page 104Get this manual
FUEL SYSTEM NOTE: The starter jet is removableUpon disassembly, place the parts in container for safe keeping
Carburetor Inspection
1Inspect jet needle and needle jet for wearLook for discoloration, shiny spots, or an area that looks different than the rest of the needleThe middle to upper portion of the needle contacts the needle jet and is the most likely wear pointIf jet needle shows signs of wear replace both the needle and needle jet to prevent rich conditionTIP: worn needle jet is difficult to spotTo check, slide slightly larger new jet needle into the needle jet and hold it to light sourceLight will be visible between the needle and needle jet if it is worn