How to Change the Coolant in a 2022 Honda CRF125FB

Shop parts for a 2022 Honda CRF125FB Dirt Bike.

Maintaining your 2022 Honda CRF125FB is essential for dependable performance on the trail. One critical but often overlooked aspect is changing the coolant. It's important to replace the coolant every two years or as specified in your owner's manual to ensure efficient engine cooling and prevent corrosion.

What You Need

  • Silicate-free coolant: Use a high-quality, motorcycle-specific coolant with corrosion inhibitors formulated for aluminum engines.
  • Basic tools: 5mm Allen key, 8mm – 10mm sockets, ratchet, Phillips screwdriver, funnel, and new crush washer for the drain bolt.
  • Shop towels & catch pan: To manage any spills.

Step-by-Step Coolant Change Guide

  1. Let the Engine Cool
    Allow the bike to cool to ambient temperature to safely service the cooling system.
  2. Remove Fairings & Covers
    Remove the left side cover by loosening Bolt A and Bolt B, then carefully disengage the prongs and tabs as described in your owner's manual. This exposes the radiator and drain bolt.
    On the right-side shroud, follow the same process if necessary to access the cap and reservoir.
    Note: The CRF125FB has plastic side panels secured by bolts and grommets. Use care when pulling them off to avoid damage.
  3. Drain the Old Coolant
    Place a catch pan under the radiator. Remove the radiator cap using a Phillips screwdriver, then loosen the drain bolt (typically located at the water pump or on the bottom of the radiator). Allow the old coolant to drain completely.
    Replace the crush washer if required.
  4. Flush the Cooling System (Optional)
    For best results, flush the system with distilled water by temporarily reinstalling the drain bolt and refilling, then repeating the drain process.
  5. Refill with Coolant
    Use a funnel to refill the radiator with silicate-free coolant until it reaches the base of the filler neck.
    Also check and fill the overflow reservoir to the indicated level.
  6. Reinstall Components
    Replace the drain bolt and radiator cap. Reinstall the side covers and shrouds securely, referencing proper alignment tabs and grommets.
  7. Bleed the System & Check Levels
    Start the engine and let it idle to circulate coolant and expel air bubbles. Watch the coolant level and refill as necessary. Allow the engine to cool and recheck levels in both the radiator and reservoir — top off if required for optimal operation.

Special Notes for CRF125FB Owners

  • This bike is known for its durable air-cooled single-cylinder engine and user-friendly chassis, making coolant maintenance straightforward. However, always use the proper coolant type to protect aluminum components.
  • Check hoses, clamps, and the radiator for leaks after servicing.
  • Proper bolt torque and accurate panel reinstallation are essential for keeping your plastics secure and avoiding rattling or lost hardware during rides.
  • Monitor your coolant reservoir after the first couple of rides for proper level — expansion and contraction may require a small top off.

Routine coolant changes keep your Honda CRF125FB running cool and reliable ride after ride. Always consult your owner's manual for torque specs and part numbers when needed for complete accuracy.

Related Shopping Categories

Shop Radiators for a 2022 Honda CRF125FB Dirt Bike.

Shop Coolant for a 2022 Honda CRF125FB Dirt Bike.

Shop Temperature Sensors for a 2022 Honda CRF125FB Dirt Bike.

Shop Tools for a 2022 Honda CRF125FB Dirt Bike.

Shop Radiator Hoses for a 2022 Honda CRF125FB 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.