How to Bleed & Replace Brake Fluid on a 2017 Kymco MXU 500i

Shop parts for a 2017 Kymco MXU 500i ATV.

This MotoSport proprietary guide walks you step-by-step through safely flushing and bleeding the brake system on a 2017 Kymco MXU 500i. Follow these procedures carefully to restore firm pedal feel and maintain braking performance. If you are unsure, consult a certified technician.

Tools & supplies

  • Correct brake fluid (use DOT4 unless the owner’s manual specifies DOT3)
  • Clear plastic tubing that fits bleeder nipples
  • Catch bottle and gloves
  • Turkey baster or fluid syringe
  • Box end wrenches (typically 8mm for bleeders; verify on your unit)
  • Brake cleaner, rags, drain pan
  • Torque wrench for caliper hardware if reinstalled
  • Assistant for manual bleeding or vacuum/pressure bleeder for one-person job

Safety first

  • Work on a level surface with the ATV secured on a stand. Wheel chocks recommended.
  • Brake fluid damages paint & plastics – wipe spills immediately and rinse with water.
  • Wear gloves & eye protection. Dispose of old fluid per local regulations.
  • Do not introduce other fluids into the system – only use specified brake fluid.

Model notes for the 2017 Kymco MXU 500i

  • The 2017 MXU 500i uses a hydraulic brake system with caliper-mounted bleeders. Verify whether your specific trim has front dual discs and rear disc or drum; procedures differ slightly for drum parking brake linkages.
  • There is no factory ABS on standard MXU 500i models — you will not need to cycle ABS modules.
  • Reservoir is located under the front plastics near the handlebar/master cylinder for the front, and a separate reservoir or a combined system may feed the rear depending on model variant. Confirm reservoir locations before starting.
  • Inspect rubber brake lines & banjo fittings for cracks & corrosion while servicing. Replace lines that show damage or excessive age.
  • If the master cylinder shows leakage or spongy return, rebuild or replace the master before bleeding new fluid.

Preparation

  1. Park ATV upright, block wheels, and remove seats/plastics as needed to access reservoirs and calipers.
  2. Clean around master cylinder reservoir caps to prevent contamination when opened.
  3. Use the turkey baster to remove most old fluid from the reservoir(s). Refill with fresh specified fluid to the full level mark.
  4. Locate bleeder nipples on each caliper and verify wrench size.

Bleeding strategy & sequence

Always bleed starting with the brake caliper farthest from the master cylinder and proceed toward the closest. For most ATVs that means:

  • 1st: Right rear (or rear caliper, if single)
  • 2nd: Left rear
  • 3rd: Right front
  • 4th: Left front (or finish with the caliper closest to master cylinder)

If your MXU has a single rear brake drum, bleed the rear wheel cylinder following the same far-to-near principle.

Manual (two-person) bleeding method

  1. Have your helper sit on the seat and lightly pump the brake lever/pedal several times, then hold steady pressure.
  2. Attach a clear tube to the bleeder nipple and submerge the other end in a catch bottle partially filled with clean fluid to prevent air re-entry.
  3. Open the bleeder about 1/4 to 1/2 turn. Fluid and bubbles will flow into the bottle. Close the bleeder before your helper releases pressure.
  4. Top up the master cylinder reservoir frequently to prevent it from running dry and drawing air into the system.
  5. Repeat until no air bubbles appear and the expelled fluid is clean. Tighten the bleeder to spec and move to the next caliper.

One-person vacuum or pressure bleeding

Use a vacuum pump on each bleeder in the same far-to-near sequence, or use a pressure bleeder on the master cylinder reservoir set to manufacturer-recommended pressure. Monitor reservoir level and fluid cleanliness while bleeding.

Final checks

  • Top the reservoir(s) to the proper level and install caps securely.
  • Pump the brake lever/pedal to confirm a firm, consistent feel. Repeat bleeding if the pedal is spongy.
  • Inspect all fittings and lines for leaks with the system pressurized.
  • Clean any spilled fluid, reinstall plastics & seats, and test the ATV at low speed in a safe area to verify braking performance.
  • Record the service date & fluid type for future maintenance intervals.

Troubleshooting & things to watch for

  • Persistent sponginess after bleeding usually indicates remaining air, a leaky master cylinder, or contaminated caliper pistons. Consider caliper rebuilds if seals are soft or leaking.
  • Discolored or gritty fluid indicates moisture contamination; full system flush is required.
  • If you find corroded banjo bolts or lines, replace them — do not reuse damaged hardware.
  • After any brake system work, perform a controlled braking test before full-speed operation.

Perform brake fluid replacement every 1-2 years or per severe-use schedules if you ride frequently in wet or heavy-duty conditions. Proper fluid maintenance preserves stopping power and extends component life on your MXU 500i.

Related Shopping Categories

Shop Brake Fluid for a 2017 Kymco MXU 500i ATV.

Shop Brake Bleeders for a 2017 Kymco MXU 500i ATV.

Shop Brake Pads for a 2017 Kymco MXU 500i ATV.

Shop Brake Lines for a 2017 Kymco MXU 500i ATV.

Shop Brake Tools for a 2017 Kymco MXU 500i 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.