How to Change the Coolant in a 2013 Kawasaki KX100
Shop parts for a 2013 Kawasaki KX100 Dirt Bike.
Maintaining your 2013 Kawasaki KX100's cooling system is vital for peak performance – especially on the track or trail. Over time, coolant degrades and its effectiveness drops, so regular replacement will keep your engine running cool and reliable. Below you'll find a proprietary MotoSport guide for changing the coolant in your KX100, along with essential model-specific tips every owner should know.
What You Need
- New coolant (silicate-free, MX/off-road compatible)
- 10mm socket or wrench
- Drain pan
- Funnel
- Shop rags
- Safety gloves & eye protection
- Optional: compressed air if flushing
Preparing Your KX100
- Ensure the engine is completely cool before you start—opening the cooling system when hot is dangerous.
- Clean the radiator cap area and drain bolt to prevent debris from entering the cooling system during service.
- Position your motorcycle upright on a stand for stability.
Draining the Coolant
- Locate the coolant drain bolt, found on the lower side of the water pump cover.
- Place a drain pan under the drain bolt.
- Slowly remove the radiator cap—this will help the coolant flow out smoothly without air locking.
- Use a 10mm wrench to remove the drain bolt and its crush washer, allowing coolant to fully drain.
- The 2013 KX100 also has a cylinder drain bolt; for a more thorough drain, remove this bolt as well. Take care not to lose the crush washers as they're small but essential for sealing.
Optional: Flushing the System
- If the coolant is especially dirty, flush the system with clean distilled water.
- You can gently pour distilled water into the radiator, reinstall the drain bolts, run the engine for a minute, then drain again.
- For complete flushing—especially when switching coolant types—use low-pressure compressed air to clear residual fluid from hoses and engine passages.
Refilling the Coolant
- Reinstall and torque the drain bolts securely. Replace crush washers if they're worn or damaged to ensure there are no leaks.
- Using a funnel, slowly pour new coolant into the radiator until it's just below the filler neck.
- Gently rock the bike side-to-side to help free air pockets in the cooling system.
- With the radiator cap off, briefly start the engine and let it idle for 20–30 seconds to circulate the coolant and release trapped air.
- Turn off the engine and top up coolant as needed.
- Install the radiator cap and wipe away any spills.
KX100-Specific Notes & Tips
- The Kawasaki KX100 features a high-output two-stroke engine with higher thermal loads than typical trail bikes – that makes fresh, high-quality coolant essential for piston and cylinder longevity.
- Always use a silicate-free coolant formulated for aluminum radiators to prevent corrosion inside the system.
- The KX100 cooling system has relatively low volume, so even a small leak or air pocket can affect cooling performance. After changing the coolant, inspect for drips and check the fluid level after your next ride.
- Routine coolant changes every 40 to 50 riding hours will help ensure consistent engine performance and extend the life of your powerplant.
Final Inspection
- Start your bike and let it reach normal operating temperature. Check for leaks around all the bolts, hoses, and the radiator cap.
- After your first ride post-service, recheck coolant levels and inspect for leaks.
Related Shopping Categories
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Shop Radiator Hoses for a 2013 Kawasaki KX100 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.