2007-2011 Polaris IQ Snowmobiles Service Manual, Page 166Get this manual
Fuel Systems Jetting Guidelines
Changes in altitude and temperature affect air density, which is essentially the amount of oxygen available for combustionIn low elevations and cold temperatures, the air has more oxygenAt higher elevations and in higher temperatures, the air is less denseVerify the production setting for your specific modelAll carburetors must be re-calibrated if operated outside the production temperature andor altitude rangeThe main jet installed in production is not correct for all altitudes and or temperaturesRefer to the jetting cart in the Specifications Chapter of this manual for correct jetting for altitudetemperature rangesNOTE: It is the owner's responsibility to ensure that the correct jets are installed in the machine for geographical areaBe very careful when jetting down in warm weatherAs the weather turns colder it will be necessary to re-jet to prevent engine damageWhen selecting the proper main jet always use the lowest elevation and temperature that is likely to be encounteredThe throttle valves are numbered 1.0, 1.5, 2.0, etc according to the size of the cutaway in millimetersThe higher the number, the leaner the gasolineair mixture