2008 Polaris ATV Outlaw 450/525 Service Manual, Page 23Get this manual
MAINTENANCE Vent Lines
Check engine, fuel tank, and carburetor vent lines for signs of wear, deterioration, damage, or leakageReplace every two yearsBe sure vent lines are routed properly and secured with cable ties
Carburetor General Maintenance
The Keihin FCR-MX 39 mm carburetor should be cleaned and properly adjusted on an annual basisRefer to the "KTM EngineCarburetion" section in the back of this service manual for carburetion maintenance detailsNormal wear from engine vibrations may cause the carburetor to supply an overly rich fuel mixtureReplace the jet needle and the needle jet after every 180 hours of operation
CAUTION
Make sure lines are not kinked or pinched