How to Replace the Brake Discs on a Polaris Sportsman

Damaged brake discs or rotors on a Polaris ATV can reduce braking power and destroy the pads. Obviously the sooner you change the rotors out, the longer the brakes will last. 

Watch the video above and follow the steps below to learn how to replace the brake discs on a Polaris Sportsman 850XP.

Tools and Parts – Polaris Sportsman Brake Disc/Rotor Change 

  • 15mm socket and drive
  • 27mm socket
  • Pliers
  • Soft blow hammer

Buy Polaris ATV brake disk

Buy Polaris ATV wheel studs

Removing Polaris Sportsman ATV Brake Discs

Step 1. Use a jack to lift the wheel off the ground and remove the tire.

Step 2. Remove the two 15mm bolts behind the brake caliper that connect it to the wheel. Next, remove the brake caliper from the brake disc and set it aside. 

Polaris Sportsman ATV brake caliper

Step 3. Use a flat-blade screwdriver to pry the dust cover in the center of the wheel loose to expose the axle bolt and cotter pin. 

Polaris Sportsman 850 XP brake caliper

Step 4. Remove the cotter pin. 

Polaris Sportsman 850 XP brake disc change

PRO TIP: If the cotter pin is fused to the axle bolt, use penetrating fluid, a hammer and pliers to remove the pin.

Step 5. Loosen and remove the axle bolt with a 27mm socket. 

Polaris Sportsman 850 brake disc removal

PRO TIP: An impact wrench is perfect for removing the bolt. Use a large pry bar to hold the wheel in place and keep it from spinning while you remove the bolt. Note the position and direction of the beveled washers behind the axle bolt. They’ll need to be replaced in the same manner to maintain tension on the bolt. 

Step 6. Use a soft-blow hammer to knock the disc and hub loose from the axle. 

Polaris Sportsman ATV brake rotor

Step 7. Use the same hammer to back the wheel studs out in order to remove the old disc. Once the old brake disc has been removed from the hub, it is time to start reversing the process.

Polaris Sportsman ATV brake rotor replacement

Replacing the Brake Discs on a Polaris ATV

Step 8. Lay the hub flat on something that leaves room for the wheel studs to come through. Line up the four holes on the new disc with the four holes on the hub, and use a soft-blow hammer to knock the studs in. 

Polaris Sportsman ATV brake disc wheel studs

Step 9. Grease the inside of the hub so that it won’t seize up if you ever have to remove it. 

Polaris Sportsman ATV brake rotor change

Step 10. Line the hub up with the end of the shaft, then gently tap the hub back into place. 

Polaris ATV brake disc rotor installation

Step 11. Replace the beveled washers in the center of the hub. 

NOTE: The inner section should be curved out toward you.

Step 12. Use a 27mm socket to retighten the axle bolt. Finish tightening it with a torque wrench to 80 foot-pounds, then replace the cotter pin in the axle bolt and reattach the dust cover. 

Polaris ATV Sportsman brake disc replacement

Step 13. Reattach the brake caliper using the two 15mm bolts. Note how the brake line is routed: over, then around, and then underneath the A-arm

Polaris Sportsman 850XP ATV brake disc change

Step 14. Replace the tire and you’re done.









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