How to Change the Coolant in a 1995 KTM 250EXC

Shop parts for a 1995 KTM 250EXC Dirt Bike.

Routine coolant changes will keep your 1995 KTM 250EXC running cooler and lasting longer on the trail. This two-stroke legend has a simple cooling circuit but correct service protects the head and seals from unnecessary heat and corrosion for years of dependable riding. Here is your MotoSport-exclusive step-by-step guide to flushing and refilling the coolant on this model, with specific notes just for the 1995 250EXC.

What Makes the 1995 KTM 250EXC Coolant System Unique?

  • Uses approximately 0.5 liters (0.13 gallons) of coolant for a full refill.
  • Features a right-side radiator bleed screw – this ensures you're not left with trapped air pockets after a change.
  • The correct coolant mix is 40 percent coolant and 60 percent distilled water for optimal cooling and antifreeze protection.

Step-by-Step Coolant Change Guide

  1. Ensure your engine is cool. Never open the radiator or drain system when hot—you risk burns from pressurized steam and hot coolant.
  2. Remove the radiator cap. This allows air to enter as coolant drains and helps the system empty completely.
  3. Locate and remove the drain screw. On the 1995 250EXC, this is usually found at the bottom of the water pump or lower radiator hose. Place a drain pan under the bike to catch old coolant.
  4. Let the coolant fully drain out. If you want a thorough flush, you can add distilled water, reinstall the drain screw, run the engine briefly, then drain again until water runs clear.
  5. Check and refit the drain screw securely. Never over-tighten—just snug it down enough to prevent leaks. Inspect O-rings for wear and replace if any cracks or flattening are seen.
  6. Prepare your fresh coolant mix. Use a high-quality, silicate-free motorcycle coolant, mixed at 40/60 with distilled water. Pre-mix it in a clean jug.
  7. Fill the left radiator with coolant. Slowly add coolant until nearly full.
  8. Bleed the system:
    • Remove the small screw on the right-side radiator. Tilt the 250EXC to the right about 30 degrees so air bubbles move up and out.
    • Continue filling until coolant escapes free of bubbles from the open screw hole. Replace and tighten the screw immediately.
    • Stand the bike upright and top off the left radiator until the coolant is about 10 mm above the radiator core fins.
  9. Start the engine with the radiator cap off. Let it idle briefly while monitoring the coolant level. Top off as needed as air works out of the system. Once stable, install the cap.
  10. Take a short ride, let the engine fully cool, and recheck the coolant level. Top up again to maintain the correct fill. Confirm there are no leaks at the drain screw or bleed screw.

Pro Tips for the 1995 KTM 250EXC

  • This model is notorious for small O-ring leaks and age-related hose fatigue. Inspect all connections and rubber when you change coolant for maximum reliability.
  • Never substitute tap water—distilled water prevents mineral build-up and corrosion especially in older radiators.
  • Use only motorcycle-specific, silicate-free coolant. Silicates can damage aluminum radiators and inner engine surfaces common to KTM two-strokes of this era.
  • After any significant maintenance, always recheck your fluid levels and monitor your engine temperature until you are certain the cooling system is trouble-free.

Final Note

With the right parts and process, changing the coolant on your 1995 KTM 250EXC is straightforward. Keeping your dirt bike cool is essential for performance and longevity. Check for leaks, refresh your coolant on schedule, and your classic KTM will keep tearing up your favorite trails for years to come.

Related Shopping Categories

Shop Radiators for a 1995 KTM 250EXC Dirt Bike.

Shop Coolant for a 1995 KTM 250EXC Dirt Bike.

Shop Temperature Sensors for a 1995 KTM 250EXC Dirt Bike.

Shop Tools for a 1995 KTM 250EXC Dirt Bike.

Shop Radiator Hoses for a 1995 KTM 250EXC 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.