How to Change the Coolant in a 2011 Yamaha YZ85

Shop parts for a 2011 Yamaha YZ85 Dirt Bike.

Keeping your 2011 Yamaha YZ85's cooling system in optimal condition is crucial for both performance and engine longevity. This guide walks you through the coolant change process, highlighting specific tips for your YZ85one of Yamaha's most popular youth motocross bikes.

What You Need

  • Fresh, compatible coolant (ready-mix motorcycle coolant recommended)
  • Distilled water (for flushing, if needed)
  • Drain pan
  • Socket wrench set
  • Funnel
  • Clean rags
  • New drain bolt gasket (recommended for each change)
  • Protective gloves

Step-by-Step Coolant Change Procedure

  1. Let the Bike Cool: Always start the procedure with a cold engine to prevent burns.
  2. Locate the Radiator Cap and Drain Bolt: The radiator cap is on top of the left side radiator. The coolant drain bolt is on the side of the water pump, located low on the right-hand side of the engine.
  3. Remove the Radiator Cap: Gradually loosen and remove the cap to release any built-up pressure.
  4. Drain the Old Coolant: Place a drain pan underneath the water pump. Use your socket wrench to loosen and remove the coolant drain bolt and its washer. Allow all old coolant to fully drain from the system.
  5. Flush the Cooling System (Recommended): Reinstall the drain bolt temporarily and fill the radiator with distilled water. Replace the radiator cap, start the engine, and let it idle for a minute or two. Turn off the engine, let it cool, then repeat the drain process. This helps flush out residual coolant and contaminants.
  6. Replace the Drain Bolt Gasket: Always use a new gasket to prevent leaks. Refit the drain bolt snuglydo not overtighten.
  7. Add New Coolant: Using a funnel, fill the radiator with fresh coolant up to the filler neck. Some bikes may require a bleed screw to be loosened to allow air outconsult your owner's manual if uncertain.
  8. Bleed the System: Lean the bike side to side gently, and press radiator hoses to help remove trapped air. Top off coolant if the level drops.
  9. Check for Leaks: Inspect around the drain bolt and radiator for leaks before replacing the radiator cap.
  10. Run the Engine: Start the bike and let it idle for a few minutes. Turn off the engine, allow it to cool, and recheck the coolant level. Top off as needed.

YZ85-Specific Notes & Tips

  • The 2011 Yamaha YZ85 is equipped with an efficient, aluminum liquid-cooled system designed for hard track riding. Keeping your coolant fresh prevents overheating and corrosioncritical for this high-revving two-stroke motor.
  • Always use coolant specifically rated for motorcycles. Car coolant can damage seals and cause premature component wear.
  • Check radiator fins for damage or blockage during every coolant servicethis bike relies heavily on airflow for effective cooling.
  • The YZ85 uses a relatively small amount of coolant. Overfilling can cause overflow; always fill to the specified level indicated in the owner's manual.

Disposal & Final Checks

  • Dispose of old coolant safelynever pour it down the drain or onto the ground. Take it to an authorized recycling center.
  • If you notice any recurring drops in coolant level, inspect the hoses, clamps, and water pump seal for potential leaks.

Routine coolant service helps you get the best performance and reliability from your 2011 Yamaha YZ85whether you're on the track or the trail. Proper cooling maintenance protects your investment and keeps you riding at your best.

Related Shopping Categories

Shop Radiators for a 2011 Yamaha YZ85 Dirt Bike.

Shop Coolant for a 2011 Yamaha YZ85 Dirt Bike.

Shop Temperature Sensors for a 2011 Yamaha YZ85 Dirt Bike.

Shop Tools for a 2011 Yamaha YZ85 Dirt Bike.

Shop Radiator Hoses for a 2011 Yamaha YZ85 Dirt Bike.

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.