2007-2008 Polaris IQ Snowmobiles Service Manual, Page 85Get this manual
Fuel Systems MIKUNI TM CARBURETOR
Function
The function of carburetor is to produce combustible airfuel mixture by breaking fuel into tiny particles in the form of vapor, to mix the fuel with air in proper ratio, and to deliver the mixture to the engineA proper ratio means an ideal airfuel mixture which can burn without leaving an excess of fuel or airWhether the proper mixture ratio is maintained or not is the key to efficient engine operationThe engine of vehicle is operated under wide range of conditions, from idling with the throttle valve remaining almost closed, to full load or maximum output with the throttle valve fully openedIn order to meet the requirements for the proper mixture ratio under these varying conditions, low speed fuel system, or pilot system, and main fuel system are provided in Mikuni type carburetorsThe Mikuni carburetor has varying operations depending upon varying driving conditionsIt is constructed of float system, pilot system, main system, and starter system or initial starting device