2008 Polaris ATV Predator 50, Sportsman Outlaw 90 Service Manual, Page 97Get this manual
FUEL SYSTEM Fuel Delivery
The throttle opening chart below demonstrates component relationship to fuel flow versus throttle valve openingThe pilot system's main function is that of low speed jetIts most effective range of fuel delivery is from idle to approximately 38 throttle valve openingThe throttle slide controls the rate of engine air by its movement up and down in the carburetor venturiAt small throttle openings the air flow is regulated chiefly by the valve cutaway, with greatest effectiveness at 14 throttle openingThrottle valves are numbered 1.0, 1.5, 2.0, etc according to the size of the cutawayDecreasing the cutaway number will increase the amount of fuel delivered in its effective rangeThe jet needle and needle jet have an effective operating range from approximately 18 to 78 throttle openingThe amount of fuel delivered during this range relies upon the jet needle clip position, as well as the needle jet size and other specificationsThe main jet affects fuel delivery at 14 throttle and consistently increases to full throttle openingTHROTTLE OPENINGTheory NOTE: Drain screw is located on the side of the float bowl12INCREASING