How to Bleed and Replace Brake Fluid on a 1999 Yamaha Bear Tracker

Shop parts for a 1999 YAMAHA BEARTRACKE ATV.

This MotoSport-exclusive guide walks you through safely draining, flushing, and refilling the hydraulic brake system on a 1999 Yamaha Bear Tracker (BearTracKE). Procedures are written for the stock single hydraulic front caliper and rear drum/hydraulic systems found on this model year. Read fully before starting and have all parts & supplies ready.

What you'll need

  • DOT 3 or DOT 4 brake fluid (check master cylinder cap label; Yamaha recommends DOT 3 on many older ATVs — DOT 4 is acceptable if compatible)
  • Clear tubing that fits snugly over bleeder nipple(s)
  • Clean catch bottle or container
  • Brake cleaner and rags
  • Wrenches: typically 8mm or 10mm for bleeder nipples; appropriate socket for caliper bolts
  • Torque wrench (for reassembly where specified)
  • Jack, stands or blocks to safely support the ATV
  • Protective gloves & eye protection

Model-specific notes for the 1999 Yamaha Bear Tracker

  • The 1999 Bear Tracker often uses a single front hydraulic disc with one bleed nipple and a rear drum brake with a cable actuated shoe plus hydraulic rear on some variants — confirm whether your rear is hydraulic before flushing.
  • Master cylinder reservoirs on this model are small & often plastic; clean the cap area thoroughly before opening to avoid contamination.
  • Rubber lines on older Bear Trackers can be brittle. Inspect hoses, fittings, and the bleeder nipple for corrosion or cracking prior to pressing hydraulic fluid through the system.
  • ABS/electronic assists are not present on this machine, so bleeding procedure is straightforward but requires attention to air pockets where hoses run through frame bends.

Safety first

  • Work on a level surface with the engine off & key removed.
  • Support the ATV securely to take weight off the wheels when opening caliper bleeders.
  • Brake fluid will damage paint and plastic. Wipe any spills immediately and use brake cleaner as needed.
  • Dispose of old brake fluid per local hazardous-waste rules.

Preparation

  1. Wash the area around the master cylinder reservoir cap. Remove the cap and diaphragm; cover the opening with clean shop towels to prevent debris from entering while you work.
  2. Check the reservoir fluid level and top with new fluid to just below the max mark. Use only the specified DOT type.
  3. Locate bleeder nipple(s): front caliper and rear caliper (if hydraulic). Rear drum hydraulic wheel cylinders may have bleeders inside the hub — remove wheel/hub covers if required to access.
  4. Attach clear tubing to the bleeder nipple and run to a catch bottle partially filled with fresh fluid to prevent air re-entry into the system.

Bleeding sequence — single-person method

Use this sequence for a front disc and hydraulic rear: rear first, then front.

  1. With the tubing attached, open the bleeder nipple approximately 1/4 turn with the correct wrench.
  2. Slowly squeeze the brake lever/pedal to push fluid out through the tubing until clear fluid (no bubbles) appears. Hold the lever/pedal down.
  3. Close the bleeder nipple while the lever/pedal remains depressed. Release the lever/pedal.
  4. Top the master cylinder reservoir as needed to prevent it running dry. Repeat the squeeze/open/close cycle until no air bubbles appear and the fluid expelled is clean.
  5. Move to the next caliper if applicable and repeat. Finish with the caliper closest to the master cylinder last for best results.

Bleeding sequence — two-person method (preferred)

  1. Person A sits on the machine and slowly applies steady pressure to the brake lever/pedal.
  2. Person B opens the bleeder nipple until fluid runs clear without bubbles, then closes it while Person A maintains pressure.
  3. Person A releases pressure. Person B repeats until fluid is bubble-free. Keep the reservoir topped between cycles.

Flushing entire system (recommended for full replacement)

  1. Start with the reservoir full of new fluid. Bleed each bleeder until fluid exiting is the new fluid color and free of bubbles.
  2. For thorough flushing, consider removing the caliper pistons slightly to move old fluid from pockets — only if you are comfortable with caliper disassembly. Rebuild seals or replace caliper components if seals are compromised.

Reassembly & final checks

  • Torque bleeder nipples and caliper mounting bolts to factory specs (consult your Yamaha service manual; if unavailable, torque caliper bolts snugly per common ATV practice then verify tightness after test ride).
  • Ensure the reservoir is filled to the correct level and reinstall cap & diaphragm.
  • Clean any spilled fluid and inspect for leaks at the bleeder, hose fittings, and master cylinder.
  • With the ATV supported, operate the brake lever/pedal several times to confirm firm feel and proper engagement.
  • Test ride at low speed to confirm braking performance before normal use.

Troubleshooting

  • Spongy brake lever after bleeding — likely air remains. Repeat bleeding, ensuring the reservoir never runs dry and hoses are not collapsed.
  • Brake lever sinks to the bar under pressure — check for internal master cylinder seal leakage or caliper piston seal failure; a rebuild or parts replacement may be needed.
  • Leaking bleeder or corroded nipple — replace nipple and clean threads; use a new copper crush washer where applicable.

Parts & maintenance tips specific to the 1999 Bear Tracker

  • Replace rubber hoses if they show cracking or soft spots. Aging hoses are a common failure point on late-1990s ATVs.
  • Keep an eye on the rear wheel hub if your model has an internal hydraulic drum — water intrusion can corrode components & contaminate fluid.
  • Master cylinder caps on older units can warp — replace the cap or diaphragm if you see swelling or leaking around the cap area.
  • Store brake fluid in a sealed container — DOT fluids absorb moisture rapidly, which degrades braking performance.

When to seek professional help

  • If brakes remain soft after multiple bleed attempts, suspect internal component failure in the master cylinder or caliper; consult a qualified technician.
  • If you encounter seized caliper pistons, severely corroded lines, or damaged reservoirs, replacement or professional rebuild is advised.

Following this MotoSport guide will restore firm, reliable braking on your 1999 Yamaha Bear Tracker when performed carefully with the correct fluid type and inspection of rubber lines & seals. Keep records of maintenance and replace aged hydraulic components proactively to prevent failures in the field.

Related Shopping Categories

Shop Brake Fluid for a 1999 YAMAHA BEARTRACKE ATV.

Shop Brake Bleeders for a 1999 YAMAHA BEARTRACKE ATV.

Shop Brake Pads for a 1999 YAMAHA BEARTRACKE ATV.

Shop Brake Lines for a 1999 YAMAHA BEARTRACKE ATV.

Shop Brake Tools for a 1999 YAMAHA BEARTRACKE 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.