2003 Polaris ATV Trail Boss 330 Factory Service Manual, Page 28Get this manual
MAINTENANCE
IDLE SPEED ADJUSTMENT
1Start engine and warm it up thoroughlyCV Carburetor
3Tighten locknut and slide boots over cable adjuster until they touch at the middle point of the adjuster4With engine running, turn the handlebars from full left to full right with transmission in neutralEngine RPM should not change and the engine should not dieIf either of these occur, return to the first step
THROTTLE OPERATION
To remove the ETC cover: 1Use medium flat blade screwdriver and insert blade into the pockets of the cover starting on the #1 position
Idle Screw
Idle Speed: 1300 100 RPM 2Adjust idle speed by turning the idle adjustment screw in (clockwise) to increase or out (counterclockwise) to decrease RPM(Refer to Illat right)NOTE: Adjusting the idle speed affects throttle cable freeplay and electronic throttle control (ETC) adjustmentAlways check throttle cable freeplay after adjusting idle speed and adjust if necessary