How to Change the Coolant in a 2022 Honda CRF150R Big Wheel

Shop parts for a 2022 Honda CRF150R Dirt Bike.

Changing the coolant in your 2022 Honda CRF150R Big Wheel is a straightforwardyet criticalmaintenance task that keeps your race-bred engine protected from overheating and corrosion. Here’s a MotoSport step-by-step guide focused on the specific needs of the CRF150RB owner.

Tools & Supplies Needed

  • Fresh, high-quality motorcycle coolant (Honda HP Coolant or equivalent, NOT automotive antifreeze)
  • 8mm socket or wrench
  • Flathead screwdriver
  • Drain pan and funnel
  • Clean rag
  • Protective gloves and eyewear

1. Preparation

  • Let the engine cool completely before you begin to avoid burns from hot coolant or engine parts.
  • Place the bike on a stable stand and ensure it is upright for accurate draining and refilling.

2. Locate & Remove the Radiator Cap

  • Remove the radiator shrouds or loosen their bolts if access is limited.
  • The radiator cap is on the left sidepress down and turn it counterclockwise to remove. Do this slowly to release any pressure safely.

3. Drain Old Coolant

  • Position the drain pan under the water pump area (bottom right side engine case).
  • Using an 8mm wrench, loosen and remove the coolant drain bolt (usually the lowest bolt on the water pump cover). A copper crush washer may come offdo not lose it.
  • Allow all coolant to drain fully. To speed up draining, slightly tilt the bike side to side.

4. Flush the System (Optional but Recommended)

  • If the old coolant was dirty or it’s been a long interval, pour fresh distilled water through the radiator to help clear out any residue. Replace the drain bolt and washer when complete.

5. Reinstall the Drain Bolt

  • Inspect the washer for damage; replace it if necessary.
  • Tighten the drain bolt securely without over-torquing (snug is sufficient for the small M6 bolt on these motors).

6. Refill with Fresh Coolant

  • Slowly pour coolant into the radiator filler neck. The 2022 CRF150RB holds approximately 0.80 US quarts (0.76 L) when empty.
  • Fill until just below the base of the filler neck. Stop periodically and gently rock the bike or "burp" the system by squeezing the radiator hoses to release trapped air.

7. Bleed Air from the Cooling System

  • Leave the cap off, start the engine, and let it idle for a minute or two. Watch as coolant level drops due to air escapingadd more if necessary.
  • Once air bubbles stop surfacing and the level settles, top off the coolant and reinstall the radiator cap securely.

8. Check for Leaks & Test Ride

  • Inspect the drain bolt and radiator for leaks.
  • After a short test ride, let the bike fully cool and recheck coolant leveladd more if needed.

Model-Specific Notes for the CRF150RB

  • The CRF150RB (Big Wheel) is competition-oriented with high engine performanceuse only motorcycle-specific, silicate-free coolant to prevent water pump seal wear and corrosion.
  • The radiator cap relief pressure is set to 1.1 kgf/cm2 to prevent boiling during hard ridingensure the cap itself is in good condition to maintain optimal system pressure.
  • Routine coolant changes (every 1-2 years or seasonally in harsh use) are vitalolder coolant loses corrosion protection and freeze resistance.
  • Never mix brands or types of coolant, as this can lead to chemical reactions, reduced cooling efficiency, and potential engine damage.

Performing regular coolant changes on your CRF150RB keeps your machine race-ready and extends its lifespantrust MotoSport for all your OEM and aftermarket coolant, service parts, and accessories.

Related Shopping Categories

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Shop Radiator Hoses for a 2022 Honda CRF150R 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.