How to Change the Coolant in a 2022 KTM 300XC TPI

Shop parts for a 2022 KTM 300XC TPI Dirt Bike.

The 2022 KTM 300XC TPI is a performance-focused two-stroke enduro machine with a unique Transfer Port Injection (TPI) system. Keeping the cooling system fresh and properly serviced is essential for optimal performance–a task that’s best done before the start of a new season, after heavy use, or if you’ve noticed your coolant level dropping or appearing dirty.

Tools & Supplies Needed

  • Fresh coolant compatible with aluminum engines (avoid silicate-based types)
  • Distilled water (for flushing)
  • Socket wrench set (including unique spline tool if replacing hoses)
  • Phillips/flathead screwdriver
  • Funnels
  • Shop rags/paper towels
  • Drain pan
  • Protective gloves

Step-by-Step Coolant Change on a 2022 KTM 300XC TPI

  1. Ensure Safety – Engine Cool
    Let the engine fully cool before opening the system to avoid potential burns.
  2. Remove the Radiator Cap
    Twist off the radiator cap on the right radiator tank. If the bike was just run, crack the cap slowly to release any pressure.
  3. Drain Old Coolant
    Place your drain pan under the right side of the engine case. Remove the coolant drain bolt (usually located on the water pump cover) and let the coolant flow into the pan.
    If equipped, open the bleed screw at the cylinder head to help the system fully drain.
  4. Flush the System
    Reinstall the drain bolt. Fill the system with distilled water through the radiator cap opening, then reinstall the cap and run the engine briefly (about 1 minute–just enough to circulate). Turn off, let cool, repeat the drain step. Repeat flushing until the drained water is clear and free of coolant color.
    This is important to prevent mixing of old and new coolant, especially if switching coolant types — TPI bikes are sensitive to contamination.
  5. Install the Drain Bolt
    Wipe and reinstall the drain bolt, torquing to factory specs.
  6. Refill with Fresh Coolant
    Using a funnel, slowly fill the radiator with new coolant. The system takes approximately 1.2 liters.
  7. Bleed Air from the System
    • On TPI bikes, air can get trapped in the cylinder head. Slightly loosen the temperature sensor on the cylinder head until coolant seeps out, then retighten the sensor once no bubbles are visible (refer to your service manual for location).
    • Tilt and gently shake the bike if needed to help release air pockets.
  8. Check and Top Off
    Reinstall the radiator cap. Start the bike, let it idle to operating temperature, then cool completely. Re-check the level and add more coolant if needed–you should see coolant at the base of the filler neck.
  9. Inspect for Leaks
    Visually inspect around all hose joints, the water pump, and the head temp sensor for any leaks. Tighten hose clamps if needed (be careful not to over-tighten if using upgraded silicone hoses).

Pro Tips for the KTM 300XC TPI Owner

  • Bleeding: TPI models are prone to air pockets in the head. Always bleed via the temp sensor–simply refilling until full isn’t enough for this model series.
  • Coolant T-Piece: The stock aluminum T-piece is a known weak point–it can break in severe crashes. Upgrading to a silicone or reinforced aftermarket T-piece during your next coolant service can reduce failure risk.
  • Check Hose Clamps: The factory clamps can loosen or be overtightened after multiple services. Consider replacing or upgrading to stainless steel band clamps if you do frequent changes.
  • Use Only Manufacturer-Recommended Coolants: Mixing types or running automotive silicate formulas can damage the water pump and radiator internals.

Maintenance Notes for 2022 KTM 300XC TPI Owners

  • The KTM TPI cooling system is compact and efficient, but requires diligence–check fluid levels before every ride, especially if riding hard or in tight woods.
  • If you notice overheating, repeated air in the system, or unexplained drops in coolant level, inspect for possible hose, T-piece, or water pump leaks.
  • Replacing hoses with reinforced silicone kits increases reliability, especially for extreme enduro or aggressive trail riding.
  • Consult your owner’s and service manual for torque specs and coolant recommendations specific to the 2022 model year.

Related Shopping Categories

Shop Radiators for a 2022 KTM 300XC TPI Dirt Bike.

Shop Coolant for a 2022 KTM 300XC TPI Dirt Bike.

Shop Temperature Sensors for a 2022 KTM 300XC TPI Dirt Bike.

Shop Tools for a 2022 KTM 300XC TPI Dirt Bike.

Shop Radiator Hoses for a 2022 KTM 300XC TPI 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.