How to bleed and replace brake fluid on a 2011 Arctic Cat 450I

Shop parts for a 2011 Arctic Cat 450I ATV.

This MotoSport exclusive service guide covers step-by-step brake fluid replacement and bleeding on the 2011 Arctic Cat 450I (450I). Follow these procedures exactly for safe, reliable braking. Read all steps before starting.

Safety & prep

  • Work on a flat, stable surface with the engine off and key removed.
  • Wear protective eyewear and nitrile gloves. Brake fluid is corrosive to paint and plastics.
  • Keep a clean rag and a container for old fluid. Dispose of fluid per local regulations.
  • Use a quality DOT 4 brake fluid (do not mix DOT 3/5 unless manufacturer allows; Arctic Cat 450I calls for DOT 4). Confirm with your owner’s manual.
  • Have replacement crush washers for banjo bolts if you remove hose fittings.

Tools & materials

  • DOT 4 brake fluid (new, unopened)
  • Brake bleeder wrench or appropriate open-end wrenches (8mm/10mm depending on bleeder size)
  • Clear vinyl tubing to fit bleeder nipple
  • Catch bottle for old fluid
  • Turkey baster or fluid syringe (optional for removing old fluid from reservoir)
  • Clean rags and parts cleaner
  • Jack or ramps and stands to safely lift ATV if needed

Model notes specific to the 2011 Arctic Cat 450I

  • The 450I uses hydraulic disc brakes front and rear. The front assembly is dual-caliper or single depending on trim; rear is a single caliper tied to the foot pedal master cylinder.
  • The master cylinder reservoir is located on the handlebar for the front brake and on the foot-pedal area for the rear. Keep these caps closed until you are ready to service each circuit.
  • There is no ABS on this model, so bleeding is straightforward linear bleeding per caliper/master cylinder sequence.
  • Some 2011 models have plastic reservoir caps with diaphragms that should be replaced if cracked or compressed. Inspect rubber diaphragms when servicing.
  • Check brake lines for aging or cracks while servicing; the OEM lines on older 450Is can harden. Replace any suspect hose to prevent failures.

Overview of the procedure

Replace fluid and bleed from the furthest caliper from each master cylinder first, then proceed closer. For the front brakes that means: right front – left front (or whichever is furthest from front master). For the rear, bleed the rear caliper(s) after the rear master.

Step-by-step: drain, refill and bleed

  1. Raise ATV safely and remove wheels as required for access to bleeder nipples.
  2. Clean around each reservoir cap and bleeder nipple to prevent contamination.
  3. Open the front master cylinder reservoir cap(s) slowly — remove diaphragm and note fluid color and level.
  4. Use a turkey baster or syringe to remove most of the old fluid from the reservoir(s) without introducing air.
  5. Top the reservoir with fresh DOT 4 fluid to the fill line. Keep cap loosely in place between steps to reduce contamination and evaporation.
  6. Attach clear vinyl tubing to the furthest caliper bleeder nipple. Place the other end submersed in a small catch bottle partially filled with fresh fluid to prevent air from being drawn back in.
  7. Have an assistant slowly squeeze and hold the brake lever/pedal. With pressure applied, open the bleeder nipple 1/4 to 1/2 turn to allow fluid and air to escape. Close the nipple before the lever/pedal is released. Repeat until fluid runs clear and free of bubbles. Replenish reservoir as needed to avoid running dry.
  8. Repeat bleeding on the next caliper in the sequence (furthest to nearest). Typical front sequence: right front, left front (verify which is furthest on your specific routing). Rear: bleed the rear caliper after front system is complete.
  9. When bleeding is complete and no air is visible in the tubing, tighten bleeder nipples to spec (snug — generally 8-12 ft-lbs for small bleeders; do not over-torque). Wipe away residue immediately.
  10. Top reservoirs to the correct level, reinstall diaphragms and caps, and clean any spilled fluid from painted surfaces. Reinstall wheels and torque axle/nut specs per manual.
  11. Test brake lever and pedal feel with ATV on stands first. Lever/pedal should feel firm and not sink. If spongy, repeat bleeding procedure.
  12. Lower ATV and perform a low-speed brake test in a safe area to confirm stopping performance before full riding.

Complete fluid replacement (when you want to flush the entire system)

  • Perform sequential bleeds while continuously topping the reservoir with new DOT 4 until expelled fluid is clear and free of dark contaminants.
  • For a full flush, remove as much old fluid from the reservoir as possible before starting so you introduce mostly new fluid into the system first.

Tips, common pitfalls & torque notes

  • Never allow the master cylinder reservoir to run dry — this will draw air into the system and require repeating the bleed.
  • Do not reuse old fluid or mix different fluid types. DOT 4 is hygroscopic — store unopened containers properly.
  • If you replace brake lines or banjo bolts, always use new crush washers and torque banjo bolts per manual; inspect for leaks under pressure.
  • If caliper pistons are seized or sticky, bleeding alone won’t fix performance — rebuild or replace the caliper.
  • Bleeder nipple torque & banjo bolt torque vary by part. If unknown, snug then incrementally tighten; avoid stripping. Consult service manual for exact torque values when available.

Post-service checks

  • Inspect for leaks at nipples, banjo bolts and reservoir seals after the first test ride.
  • Recheck fluid levels after a short break-in ride; top as needed.
  • Record the service date and mileage. Brake fluid should be replaced every 2 years or per severe-use schedule if you ride in wet/muddy conditions frequently.

If you need OEM-quality parts, seals or replacement hoses specific to the 2011 Arctic Cat 450I, MotoSport stocks model-specific items to keep your brakes performing at their best.

Related Shopping Categories

Shop Brake Fluid for a 2011 Arctic Cat 450I ATV.

Shop Brake Bleeders for a 2011 Arctic Cat 450I ATV.

Shop Brake Pads for a 2011 Arctic Cat 450I ATV.

Shop Brake Lines for a 2011 Arctic Cat 450I ATV.

Shop Brake Tools for a 2011 Arctic Cat 450I ATV.

Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.