How to Bleed & Replace Brake Fluid on a 2019 Honda TRX500 Foreman 4X4 (FM1)

Shop parts for a 2019 Honda TRX500FORE ATV.

This MotoSport procedural guide covers draining, replacing, and bleeding the brake fluid on your 2019 Honda TRX500 Foreman 4X4 (FM1). Follow these steps carefully to maintain braking performance. This guide is written specifically for the TRX500 FM1 layout — the machine uses a handlebar front master cylinder and a foot-operated rear master cylinder with separate reservoirs. Confirm the brake fluid type marked on each reservoir cap and the owner's manual before starting.

Tools & Supplies

  • Honda-approved DOT 3 brake fluid (or DOT specified on your reservoir cap & in the owner's manual)
  • Clean clear tubing that fits bleeder nipples
  • Brake fluid catch container
  • Wrench for bleeder nipples (typically 8mm or 10mm; confirm by inspection)
  • Syringe or turkey baster for reservoir removal of old fluid
  • Hand pump vacuum bleeder or two-person pump method
  • Shop rags, isopropyl alcohol for cleanup
  • Latex gloves and eye protection
  • Torque wrench (for any caliper fasteners if removed)

Model Notes & Safety

  • The TRX500 FM1 has two separate hydraulic circuits: front (handlebar lever) and rear (foot pedal). Bleed each circuit separately.
  • Brake fluid is hygroscopic — once opened it absorbs moisture. Use fresh, unopened fluid. Do not reuse drained fluid.
  • Avoid spilling fluid on painted plastic and bodywork — it damages finish. Clean spills immediately with water & isopropyl alcohol.
  • If you plan to remove calipers or rotate hoses, note torque specs in the service manual and inspect pads, rotors, hoses & banjo bolts for wear/leaks.

Preparation

  • Park on level ground, secure the ATV, and block the wheels. Work with the engine off, key removed.
  • Clean the area around each reservoir cap to prevent contamination.
  • Place drip pans under calipers and bleeder valves.
  • Remove master cylinder reservoir caps, diaphragms, and strainers if equipped. Inspect for contamination or sludge.

Step 1 – Remove Old Fluid from Reservoirs

  • Use a syringe or turkey baster to extract as much old fluid from each reservoir as possible. Do not push fluid back into the lines.
  • Refill the reservoirs with fresh brake fluid to the specified level. Keep the cap off but sealed with a clean, lint-free rag to limit contamination.

Step 2 – Decide Bleeding Method

Two reliable methods: two-person pump method or a vacuum/pressure bleeder. A vacuum or pressure bleeder is faster and reduces air ingestion. Regardless of method, always keep the reservoir topped up during the process.

Step 3 – Bleeding Order

Bleed each circuit separately. For the TRX500 FM1 follow this order for each circuit:

  • Identify all calipers connected to the circuit. For front: usually both front calipers. For rear: the rear caliper.
  • Start with the caliper farthest from the corresponding master cylinder and work toward the closest. For example, if the front master supplies two front calipers, bleed the farthest front caliper first, then the nearer one.

Step 4 – Bleeding Procedure (Two-Person)

  1. Attach clear tubing to the bleeder nipple and the other end into a catch jar partially filled with fresh fluid (prevents air from re-entering).
  2. One person depresses the brake lever/pedal gently several times and holds it down. The other person opens the bleeder nipple about a quarter-turn to let fluid and air out, then closes the nipple before the lever/pedal is released. Repeat until no air bubbles appear and the fluid runs clear.
  3. Keep topping the reservoir so it never runs near empty during the process.
  4. After bleeding that caliper, tighten the bleeder nipple, wipe clean, and move to the next caliper in the sequence.

Step 5 – Bleeding Procedure (Vacuum or Pressure Bleeder)

  1. Attach the vacuum hose or pressure cap to the reservoir per the tool instructions.
  2. Open the bleeder nipple and run the tool until clear, bubble-free fluid flows. Close the nipple while still under vacuum/pressure to avoid drawing air back into the system.
  3. Repeat for each caliper following the farthest-to-closest order.

Step 6 – Final Checks

  • Ensure each bleeder nipple is tightened to the appropriate snugness (do not overtighten) and wiped clean.
  • Top reservoirs to the specified level, reinstall diaphragms and caps, and secure them.
  • Operate the brake lever and pedal multiple times to confirm a firm, consistent feel. If the lever/pedal feels spongy, repeat bleeding.
  • Inspect for leaks at banjo bolts, bleed nipples, and hose connections after applying pressure to the brakes.

What to Inspect While Servicing

  • Brake pads: remaining thickness and even wear.
  • Rotors: scoring, warpage & runout.
  • Brake lines & hoses: cracks, swelling, or leaks. Replace any rubber hose older than recommended service interval or with visible damage.
  • Banjo bolt washers: replace crush washers whenever removing fluid fittings to prevent leaks.

Disposal

Dispose of used brake fluid per local hazardous-waste regulations — do not pour it down drains or into the environment.

Troubleshooting

  • Persistent spongy lever after proper bleeding: check for internal master cylinder seal failure or hose expansion; perform pressure test or bench-check master cylinder.
  • Brake drag after bleeding: check caliper pistons & slide pins for proper retraction and lubrication.
  • If air keeps returning into the system: inspect for leaks at fittings, damaged hoses, or a cracked master cylinder housing.

Torque & Reference Notes

When re-installing any brake hardware, follow Honda torque specs from the factory service manual for banjo bolts, caliper mounting bolts, and reservoir fasteners. If you don't have the manual, contact MotoSport for OEM parts & manuals for your 2019 TRX500 FM1.

If you notice unusual brake behavior after bleeding — soft pedal/lever, dragging brakes, or visible leaks — stop riding and address the issue before use.

Related Shopping Categories

Shop Brake Fluid for a 2019 Honda TRX500FORE ATV.

Shop Brake Bleeders for a 2019 Honda TRX500FORE ATV.

Shop Brake Pads for a 2019 Honda TRX500FORE ATV.

Shop Brake Lines for a 2019 Honda TRX500FORE ATV.

Shop Brake Tools for a 2019 Honda TRX500FORE 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.