How to Change the Coolant in a 2021 GAS GAS MC 450F

Shop parts for your ride now!

Routine coolant changes are crucial for maintaining the high performance and longevity of your 2021 GAS GAS MC 450F. This exclusive MotoSport.com guide will walk you through the process step-by-step, while highlighting model-specific details and recommendations.

What You Need

  • Fresh coolant suitable for off-road motorcycles
  • Drain pan
  • Socket wrench set
  • Funnel
  • Protective gloves and goggles
  • Clean rags

Before You Begin

  • Let the engine cool completelyworking on a hot cooling system can lead to burns from hot coolant or steam.
  • Work in a well-ventilated area and secure your bike using a proper stand or tension straps to prevent tipping.
  • The MC 450F has direct-access radiators positioned high on the frame, making service straightforward but requiring care to avoid damage to radiator fins and hoses.

Step-by-Step Coolant Change Procedure

  1. Remove the Skid Plate or Side Panel (if installed):
    For easier access to the drain bolt and radiators, remove any plastic covers or guards obstructing your work area.
  2. Locate and Open the Radiator Cap:
    Remove the radiator cap to allow air into the system and help the coolant drain more quickly. The cap is found on the top of the left radiator.
  3. Drain the Old Coolant:
    Position your drain pan beneath the water pump (right side of the engine). Locate the coolant drain bolt at the base of the water pump covertypically a 10mm or 12mm bolt. Loosen and remove the bolt, allowing the coolant to fully drain.
    Tip: Tilting the bike gently can assist with a complete drain, but do so carefully to avoid spills.
  4. Flush the Cooling System (Recommended):
    For best results, briefly flush the radiators with distilled water to remove residue, then let all liquid drain completely. Never use hard or tap water, as mineral deposits can affect cooling efficiency.
  5. Replace the Drain Bolt:
    Clean the threads, inspect the washer, and reinstall the drain bolt securely. Avoid overtightening to prevent stripping the threads.
  6. Add New Coolant:
    With a funnel, slowly fill the radiator with fresh coolant until it reaches the top of the filler neck. The MC 450F system holds about 1.0 liter, but always fill as specified on your tank and check the level as you pour.
    Model note: Always use a high-quality, ready-to-use engine coolant with propylene glycol that offers aluminum protection and anti-corrosive properties for off-road racing environments.
  7. Bleed the System:
    Slowly rock the bike side to side to eliminate air pockets. Some models have a bleed screw on the cylinder headif yours does, open it briefly until coolant flows steadily, then close. Recheck and top off the coolant if necessary.
  8. Reinstall the Radiator Cap:
    Once the coolant is level and free of bubbles, reinstall the cap securely.
  9. Reattach Any Covers or Guards:
  10. Start and Warm Up the Engine:
    Idle the bike for a few minutes, then check the coolant level again with the engine off and cool. Top off as needed.

Important Model Specific Notes

  • Use only the manufacturer-recommended coolant type– avoid mixing with other coolant bases, especially if switching from water-based to non-water based formulas, as this can cause gelling or corrosion.
  • Always inspect radiator hoses and clamps for wear or leaks during this service. Replace damaged parts to maintain performance.
  • The MC 450F's aluminum radiators and high-flow system are designed for extreme off-road use, making proper coolant maintenance critical for engine longevity and reliable track performance.
  • If coolant contacts your skin or eyes, flush immediately with water and consult a medical professional as needed.

When to Change Your Coolant

  • Change coolant at least once a year or every 40–60 hours of operation (more often if riding in sand, mud, or extreme heat).

Now your 2021 GAS GAS MC 450F is ready to take on your next ride with a fresh dose of reliable cooling power. Regular maintenance keeps you on the track—and off the sidelines.

Related Shopping Categories

Shop Radiators for Your Ride

Shop Coolant for Your Ride

Shop Temperature Sensors

Shop Tools

Shop Radiator Hoses for Your Ride

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.