How to Change the Coolant in a 2013 Kawasaki KX85: A Complete MotoSport Guide
Shop parts for a 2013 Kawasaki KX85 Dirt Bike.
Regular coolant changes help your 2013 Kawasaki KX85 run cooler, last longer, and perform its best on or off the track. Follow this exclusive MotoSport.com step-by-step guide designed specifically for your MMY dirt bike.
Why Coolant Changes Matter for the KX85
The KX85 is a high-performance, race-inspired 2-stroke, and its engine operates at high RPMs. Timely coolant changes prevent mineral buildup, overheating, and internal corrosion–all critical for extending the life of power valves and maintaining cylinder health in this model.
What You Need
- Coolant compatible with aluminum engines (silicate-free)
- Drain pan
- 10mm or 12mm wrench
- Funnel
- Compressed air (optional for thorough flushing)
- Shop towels
- New crush washer for drain bolt (recommended)
- Safety gloves & eye protection
Step-By-Step Instructions
-
Allow the bike to cool completely.
Never open a hot radiator—wait until the engine is fully cool and pressure-free. -
Remove the radiator cap.
Twist the cap off slowly to relieve remaining pressure. -
Position a drain pan under the engine.
The main coolant drain bolt is typically on the water pump cover at the lower right side of the engine. On the KX85, there is also a secondary drain bolt on the side of the cylinder. Use your wrench to loosen the drain bolts and allow coolant to drain fully.
Tip: Replace the drain bolt crush washer for a reliable seal during reassembly. -
Flush the cooling system (optional but recommended).
For best results, remove a radiator hose and pour distilled water or blow compressed air through the radiator and cylinder to remove any residual old coolant and debris. Ensure all water or residue is cleared out before adding new coolant. -
Reinstall drain bolts securely.
Tighten by hand first to avoid cross-threading, then snug gently with your wrench. -
Fill the radiator.
Using a funnel, slowly add fresh coolant to the top of the radiator until it reaches the base of the fill neck. -
Bleed air from the system.
Gently rock the bike side to side, and add more coolant if the level drops. For a thorough job, open the small air bleed screw (if equipped) until coolant escapes – then retighten. -
Replace the radiator cap and wipe up spills.
Make sure the cap clicks into place securely. -
Start the engine and warm it up.
Let the bike idle until the cooling system cycles. Shut off, let cool, and re-check coolant level – top off if needed.
Special Notes for KX85 Owners
- The 2013 KX85 uses a high-revving 2-stroke cylinder–avoid running pure water or automotive coolant, since specialized dirt bike coolants better manage localized hotspots and stop cavitation.
- Watch closely for leaks after your first ride, especially around drain bolts and hoses you touched during service.
- If you ride hard or compete, consider more frequent coolant changes for optimal protection.
- Whenever you change coolant, inspect radiator fins for damage, clear away mud, and ensure the fan (if equipped) spins freely.
- Use only high-quality, OEM-compatible coolants to protect magnesium and aluminum components unique to the KX85 engine.
Final Advice
Changing your coolant is quick and straightforward, but overlooking it can cost you critical performance or even an engine. Regular cooling system maintenance is one of the best ways to protect your investment and ensure your KX85 stays race-ready season after season.
Related Shopping Categories
Shop Radiators for a 2013 Kawasaki KX85 Dirt Bike.
Shop Coolant for a 2013 Kawasaki KX85 Dirt Bike.
Shop Temperature Sensors for a 2013 Kawasaki KX85 Dirt Bike.
Shop Tools for a 2013 Kawasaki KX85 Dirt Bike.
Shop Radiator Hoses for a 2013 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.