How to Change the Coolant in a 2020 Honda CRF450R: MotoSport.com Guide
Shop parts for a 2020 Honda CRF450R Dirt Bike.
Changing the coolant on your 2020 Honda CRF450R is a crucial part of routine maintenance, ensuring peak performance and optimal engine temperature on and off the track. As with any high-performance motocross bike, proper coolant service helps prolong the life of engine components and maintains consistent operating temperatures whether you’re hitting doubles or tearing up a technical trail. This proprietary MotoSport guide will walk you through every step tailored for your model – including special considerations just for the 2020 CRF450R owner.
Tools & Supplies You’ll Need
- Metric socket set and ratchet (10mm recommended)
- Drain pan
- Coolant rated for aluminum engines (silicate-free – check your manual for spec)
- Distilled water (for flushing, if required)
- New copper crush washer for the drain bolt
- Shop rags or paper towels
- Safety gloves and eye protection
Step-by-Step Coolant Change Procedure
- Ensure the bike is completely cool. Never open the radiator cap or perform coolant service on a hot engine to avoid burns or pressurized coolant spray.
- Remove your shrouds and engine guard (if fitted). The 2020 CRF450R requires removing these for best access to the radiator and water pump. Use a 10mm socket to remove the engine guard bolts and any fasteners holding radiator shrouds. Remember to route the radiator overflow hose properly during reassembly.
- Place a drain pan underneath the water pump. Locate the coolant drain bolt at the bottom of the water pump cover (typically the lowest bolt).
- Remove the radiator cap. This allows the coolant to drain faster and more completely.
- Remove the coolant drain bolt and washer. Carefully loosen and remove the bolt – coolant will start draining immediately. Allow all coolant to fully empty into your drain pan.
- Inspect and replace the crush washer. Always install a new copper crush washer on the drain bolt to prevent leaks.
- Reinstall and torque the drain bolt. Honda recommends a torque setting of 10 N·m (7 lbf·ft). Tighten the bolt evenly to ensure a proper seal.
- If flushing is necessary, fill the radiator with distilled water, reinstall the cap and run the engine briefly; then repeat the drain process to ensure old coolant is fully removed. Skip this step for regular coolant changes if previous coolant was in good condition.
- Fill the system with the specified coolant. Slowly pour the new coolant into the radiator until it reaches the filler neck.
- Bleed trapped air. Gently rock the bike and squeeze the lower radiator hose to help any air bubbles escape. Some owners prefer to start the engine for 30 seconds with the radiator cap off, then top off the coolant as needed, but do not let the coolant surge violently or overflow.
- Refit the radiator cap. Clean any spills, reinstall the engine guard and plastic shrouds, and confirm the overflow hose is routed correctly – this is critical for the 2020 CRF450R’s frame design.
- Start the engine and let it warm up. Watch for leaks and monitor the coolant level. As the engine cools, check the coolant level once again and top off if needed.
2020 CRF450R Model-Specific Notes
- The 2020 CRF450R features a high-capacity radiator system and a unique frame-integrated overflow routing. Be sure excess coolant escapes via the overflow tube at the bottom of the frame, and don’t overfill the radiator or reservoir as this can lead to overflow during heat expansion.
- Only use coolant approved for aluminum motorcycle engines to avoid corrosion or seal damage.
- Look out for signs of coolant loss or overheating; repeated overflow may indicate a compromised radiator cap, hose, or head gasket.
- Honda recommends changing coolant at least every two years, or as needed for severe or race conditions.
Responsible Disposal & Final Check
- Dispose of old coolant at a local hazardous waste facility. Never pour coolant onto the ground or into drains.
- Always double-check coolant level after your first ride, as trapped air may work its way out with engine heat.
Keeping your 2020 Honda CRF450R’s cooling system serviced with MotoSport parts ensures reliable performance every ride. For more essential maintenance tips and OEM-grade parts, MotoSport has your back—on and off the track.
Related Shopping Categories
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Shop Radiator Hoses for a 2020 Honda CRF450R 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.