2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 127Get this manual
CARBURATION AND FUEL SYSTEM Throttle Opening vsFuel Flow
In full throttle condition the cross sectioned area between the jet needle and the needle jet is larger than the cross sectioned area of the main jetThe main jet therefore has greater control over fuel flowSmall Clearance Medium Clearance Large Clearance
2Remove float bowlRemove the float pin screwThe float and float pin can be removed
3Remove inlet needle seat retaining screw along with plate, and carefully remove needle seatNOTE: Do not use pliers to remove the seat or permanent damage may occurClosed Throttle One-half Throttle Full Throttle