2004 Polaris Pro X Factory Service Manual, Page 71Get this manual
MAINTENANCE Brake System
Inspection
The brake lever reserve should be inspected frequentlyMeasure the clearance between the lever and handlebar gripInspection should be made with the lever firmly depressedLever reserve (A) should be no less than 12 (1.3 cmReplacement of brake pads will be necessary when the brake pad material is thinner than the backing plate (approximately 116 (1.6mm))
Hydraulic Brake
Excessive Lever Travel
The snowmobile's hydraulic brakes are self-adjustingIf excessive brake pad clearance should develop, the caliper must be disassembled, cleaned, and repaired
Caliper Backing
Chaincase
Pad Disc