How to Change the Oil in a 2021 GAS GAS EX 450F — MotoSport.com Expert Guide

Shop parts for a 2021 GAS GAS EX 450F Dirt Bike.

Regular oil changes are essential for keeping your 2021 GAS GAS EX 450F running at peak performance and extending the life of your engine. This guide provides a comprehensive, step-by-step walkthrough, essential tools, and specific model tips to ensure a fast, clean, and reliable oil change every time.

Tools and Materials Needed

  • 1.2 liters of Motorex Cross Power 4T 10W/50 full synthetic oil (OEM recommended)
  • 1 OEM oil filter
  • 1 oil drain bolt crush washer
  • 10 mm and 13 mm T-handle wrenches or sockets
  • 5 mm Allen wrench
  • Pliers or snap ring pliers (for oil screens)
  • Drain pan
  • Contact cleaner
  • Funnel
  • Measuring cup (optional, to verify oil amount)
  • Safety glasses and gloves
  • Rags or shop towels

Complete oil change kits are available that include all required parts and save time gathering supplies.
Tip: Warm up your motorcycle for a few minutes before starting; this helps the oil drain faster and more completely.
Kit availability example:

  • GAS GAS OIL CHANGE KIT (1.2 L), includes correct oil, OEM filter, and crush washer for 2021 GAS GAS EX 450F

Step-by-Step Oil Change Instructions

  1. Preparation:
    • Warm up your EX 450F for 2-3 minutes to ensure the oil flows easily.
    • Turn off the engine and place the bike upright on a stand.
    • Remove the skid plate, if equipped, using appropriate tools. This gives access to the drain plugs.
    • Put on safety glasses and gloves to protect against spilled oil.
  2. Drain the Old Oil:
    • Clean the area around all three drain locations (main oil drain plug, oil screen cover, and secondary drain plug).
    • Place your drain pan underneath the engine.
    • Using a 13 mm wrench, remove the main oil drain bolt (typically on the lower rear of the engine).
    • Allow oil to fully drain into the pan.
    • Use pliers or snap ring pliers to remove the left-side oil screen cover and pull out the oil screen.
    • Remove any additional secondary drain plug (check manual for exact location; often a 5 mm Allen bolt).
    • Thoroughly clean all screens with contact cleaner and a rag, reinstall when dry.
  3. Replace the Oil Filter:
    • Locate the oil filter cover (typically right side of the engine). Remove the cover bolts with a 10 mm wrench or socket.
    • Remove and discard the old oil filter.
    • Wipe the filter cavity with a clean rag.
    • Install the new OEM oil filter (ensure it is oriented correctly as per the owner's manual for proper oil flow).
    • Reinstall the cover and torque bolts to manufacturer specs.
    • Replace the oil drain crush washer with a new one and reinstall the drain bolt. Torque to spec.
  4. Refill with Fresh Oil:
    • Install your funnel in the oil fill port on the top side of the engine (right side).
    • Pour in 1.2 liters of Motorex Cross Power 4T 10W/50 full synthetic oil, as specified for this engine.
    • Reinstall the oil fill cap.
  5. Check for Leaks and Correct Oil Level:
    • Start the engine and let it idle for 1-2 minutes.
    • Turn off the bike and inspect for leaks around the drain plug and oil filter area.
    • Check the oil level via the sight glass (if equipped) or dipstick. Add small amounts if needed, but do not overfill.
  6. Clean Up and Dispose of Oil Properly:
    • Reinstall the skid plate.
    • Wipe down any spilled oil and clean your work area.
    • Dispose of old oil and filter at a certified recycling center.

Model-Specific Call-Outs for the 2021 GAS GAS EX 450F

  • The engine oil capacity is 1.2 liters for this specific model year, which is slightly different from some older or smaller displacement GAS GAS bikes.
  • Always use full synthetic 10W-50 oil as recommended by the manufacturer for the EX 450F.
  • Oil screens (not just the filter) should be removed and cleaned at every oil change for best engine longevity.
  • This model shares oil change procedure similarities with other late model KTM/Husqvarna/GasGas 450-501 bikes, making some universal dirt bike tools applicable.
  • The owner's manual recommends changing the oil and filter, and cleaning both oil screens, as part of each service interval (varying by riding conditions, but typically every 10-15 hours for aggressive riding).

Final MotoSport.com Pro Tips

  • Do not overtighten drain plugs or oil filter covers—use a torque wrench when possible.
  • Get a quality oil change kit to streamline your maintenance and avoid running short on oil or forgetting small parts.
  • Keep service records to track your maintenance intervals and help resale value.
  • For sand or race conditions, consider more frequent oil changes as recommended in the official manual.

Maintaining your 2021 GAS GAS EX 450F with regular oil changes is the best investment you can make in your bike’s longevity and ultimate performance. Find all genuine parts and tools you need at MotoSport.com for the smoothest maintenance experience.

Related Shopping Categories

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Shop Tools for a 2021 GAS GAS EX 450F Dirt Bike.

Shop Oil Fillers and Drain Plugs for a 2021 GAS GAS EX 450F 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.