How to Change the Coolant in a 1996 Honda CR125
Shop parts for a 1996 Honda CR125 Dirt Bike.
Maintaining proper coolant in your 1996 Honda CR125 is essential for peak performance and engine longevity. Coolant not only regulates engine temperature but also prevents internal corrosion in a bike that's built to handle the rigors of motocross. Changing the coolant is a straightforward job, but a little extra care goes a long way, especially on a model as iconic and high-revving as the CR125.
What You'll Need
- Fresh coolant (look for motocross/dirt bike-compatible types, especially those safe for aluminum components)
- A drain pan
- Socket set (8mm – 12mm sizes for plastics, tank, and hoses)
- Flathead screwdriver or pliers (for hose clamps)
- Compressed air (optional, for flushing)
- Clean rag
- Distilled water (if you choose to flush with water)
Steps to Change Coolant on a 1996 CR125
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Prep the Bike:
Ensure your CR125 is cool before you begin. Place the bike on a stand for stability. Remove the seat, side plastics, and fuel tank to access the radiators and hoses. This is especially helpful for CRs, which can be tight around the radiators.
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Locate & Open the Radiator Cap:
The cap is on top of the left radiator. Loosen the cap, but do not remove it fully until you're ready to drain fluid – this avoids unexpected sprays if there's pressure built up.
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Drain the Old Coolant:
On the lower water pump cover, locate the coolant drain bolt (usually 8mm). Position your drain pan underneath, then remove the bolt. Let all coolant flow out. Remove the lowest radiator hose to ensure complete draining. Tilt the bike gently if necessary.
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Flush the System (Recommended):
If your coolant looks dirty or you're switching types, flush the system. Reinstall the drain bolt and fill the system with distilled water. Loosen hoses and use compressed air to clear out traces of old coolant, especially if switching from water-based to a non-water-based coolant. Never leave tap water inside – always use distilled to prevent mineral deposits.
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Inspect Components:
Check hoses and clamps for wear or bulging. The 1996 CR125's high-rpm nature can fatigue hoses quicker. Also, inspect the radiator cap – a weak spring or cracked seal can cause overheating or coolant loss. Replace parts as needed.
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Reinstall & Refill:
Reattach all hoses, tighten hose clamps, and install the drain bolt with a fresh washer if necessary. Slowly fill the left radiator with new coolant, rocking the bike gently to release trapped air. Stop at the base of the radiator neck.
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Bleed Air & Top Off:
With the bike upright, briefly loosen a hose clamp or squeeze the hoses to help purge air. Start the engine and let it idle for a few minutes with the radiator cap off. Add coolant as needed until it stays steady. Shut off the engine, let it cool, and check the level again.
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Final Reassembly:
Replace the radiator cap firmly. Reinstall the tank, plastics, and seat. Wipe any spilled coolant from the engine or frame.
CR125 Model-Specific Notes
- The 1996 CR125 is legendary for its top-end power and high-revving two-stroke nature. This means it generates more sustained heat than many thumper bikes—always use fresh, oxygenated coolant, especially in hot riding conditions.
- The radiators are somewhat exposed on this era CR. Inspect fins for damage and keep debris clear to maximize cooling efficiency. The mounting brackets can develop fatigue—inspect regularly for cracks or looseness.
- Honda recommends checking for leaks after the first ride and after each coolant change, as aging hoses can shrink or split, especially after reinstallation.
- If you ever notice excessive coolant loss or overflow during hard rides, check the radiator cap and head gasket—both are common culprits for sudden coolant system issues on older two-strokes.
Final Tip
Monitor the coolant level carefully for your next few rides. Always carry extra coolant in your gear bag–a minor leak can quickly turn into an overheating situation on a race day.
Related Shopping Categories
Shop Radiators for a 1996 Honda CR125 Dirt Bike.
Shop Coolant for a 1996 Honda CR125 Dirt Bike.
Shop Temperature Sensors for a 1996 Honda CR125 Dirt Bike.
Shop Tools for a 1996 Honda CR125 Dirt Bike.
Shop Radiator Hoses for a 1996 Honda CR125 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.