How to Change the Coolant in Your 2020 Kawasaki KX85: Complete MotoSport Guide
Shop parts for a 2020 Kawasaki KX85 Dirt Bike.
Keeping the cooling system in your 2020 Kawasaki KX85 in top condition is crucial for peak performance and engine longevity. This MotoSport-exclusive guide walks you through the correct process to drain, flush, and refill your KX85's coolant–no shortcuts, no guesswork. Whether you're maintaining your race machine or getting prepped for the next trail ride, follow this step-by-step procedure built for KX85 owners.
Noteworthy Features of the 2020 KX85
- High-revving 2-stroke engine runs hot, making cooling system maintenance especially important.
- Dual radiator setup provides efficient cooling, key for aggressive riders and sustained sessions.
- Relatively small coolant capacity means even minor fluid loss can quickly impact performance.
- For this year and model, always use coolants safe for aluminum components, free from silicates and phosphates.
Supplies & Tools You'll Need
- Manufacturer-approved premixed coolant or distilled water plus coolant concentrate
- 8mm socket or wrench (drain bolt)
- Phillips screwdriver (sometimes needed for bleed screw or shrouds)
- Catch pan
- Clean funnel
- Shop rags
- New sealing washer for drain bolt (recommended)
- Torque wrench (optional)
Step-by-Step Coolant Change Guide
- Prep your KX85: Make sure the engine is completely cool. Remove the seat and any radiator shrouds for easier access.
- Remove the radiator cap: Loosen the radiator cap slowly to relieve pressure. Removing the cap first allows complete drainage and avoids vacuum lock.
- Locate and remove the drain bolt: The KX85's coolant drain bolt is typically on the water pump cover (right engine case). Place your catch pan under the bolt, then remove it using the 8mm socket. Allow coolant to fully drain.
- Drain the cylinder (if equipped): Some KX85 models have a small bolt (cylinder drain) on the cylinder. Remove it to ensure all old coolant exits the system.
- Flush if necessary: If your coolant is contaminated or you're switching types, flush the system with distilled water. Replace all bolts and briefly refill and drain until only clean water exits.
- Inspect, clean, and reinstall: Check the drain bolt washer. Replace if worn for a leak-free seal. Wipe away any residue, then reinstall both the cylinder and main drain bolts snugly.
- Refill with new coolant: Slowly pour in the new coolant using a funnel at the radiator neck to avoid air bubbles. Fill until the coolant is visible at the neck.
- Bleed air from the system: On the KX85, tilt the bike gently side-to-side and lightly tap on hoses to help bubbles escape. Some models include a bleed screw on the radiator; open it briefly until only coolant flows, then close.
- Top off & run the engine: Refit radiator cap loosely. Start the bike and let it idle for 2–3 minutes, revving lightly to circulate coolant. Shut down and allow to cool.
- Final top-off and inspection: Once cool, remove the radiator cap again. Add coolant if needed to reach the filler neck. Check for leaks at drain bolts and the radiator.
Model-Specific Tips
- NEVER substitute automotive antifreeze. Only use premixed or mix-it-yourself coolants safe for aluminum race engines without silicates or phosphates.
- Always maintain the correct coolant level. The KX85 runs hotter than many trail bikes, and low coolant will quickly cause overheating or even seizure.
- Check hoses and clamps each time you change coolant; the KX85's vibration can loosen clamps over time.
- Dispose of old coolant responsibly. Ethylene glycol is toxic—never pour it down the drain or on the ground.
When to Change Coolant
- Kawasaki recommends refreshing the coolant at least once every two years, or annually for race/competition use.
- Change immediately if the fluid is discolored, contaminated, or after any major engine work.
Changing the coolant in your 2020 Kawasaki KX85 is straightforward but vital for keeping your two-stroke running strong. Protect your engine, enhance performance, and give yourself track-ready peace of mind with simple proactive care–the MotoSport way.
Related Shopping Categories
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Shop Coolant for a 2020 Kawasaki KX85 Dirt Bike.
Shop Temperature Sensors for a 2020 Kawasaki KX85 Dirt Bike.
Shop Tools for a 2020 Kawasaki KX85 Dirt Bike.
Shop Radiator Hoses for a 2020 Kawasaki KX85 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.