How to Change the Oil in a 2009 Yamaha WR450F — MotoSport.com Guide

Shop parts for a 2009 Yamaha WR450F Dirt Bike.

Regular oil changes are essential to keep your 2009 Yamaha WR450F performing at its best. In this guide, you’ll find all the information, tools, and model-specific tips you need to do the job right and keep your dirt bike in top condition.

Tools and Supplies Needed

  • Socket set (8mm, 10mm, 12mm sockets and ratchet)
  • Box wrench (12mm recommended for drain plug)
  • Oil drain pan
  • New oil filter (specific to 2009 WR450F)
  • New engine oil (Yamaha recommends 10W-40, confirm in owner’s manual; you’ll need about 1.0 liters/1.06 quarts for filter change)
  • Funnel
  • Replacement copper washer (for drain plug)
  • Clean rags
  • Safety gloves
  • Service manual (for reference)

Steps to Change the Oil

  • Warm up the engine
    • Start and idle the engine for 4–5 minutes. Warm oil flows easily and helps carry away contaminants. Avoid idling too long — the auto-stop system may engage after seven minutes on newer models.
  • Remove the skid plate
    • Unbolt the three 8mm bolts securing the skid plate. Set aside the bolts and the plate.
    • Older models and aftermarket plates may use different fasteners, so check yours.
  • Loosen the dipstick/filler cap
    • This step vents the crankcase, allowing oil to drain more thoroughly. The dipstick is typically located on the right side of the bike.
  • Position your drain pan
    • Place a drain pan beneath the drain plug under the engine.
  • Remove the drain bolt and crush washer
    • Use your 12mm wrench or socket to unbolt the engine drain plug (located on the right, rear part of the crankcase).
    • Be careful: Oil may be hot.
    • Let the oil drain completely.
    • Replace the copper washer on the drain bolt. Reusing an old washer can cause leaks.
  • Remove and replace the oil filter
    • With your drain pan still in place, remove the oil filter cover (three 8mm bolts).
    • Take out the old oil filter and clean the chamber with a rag.
    • Install a new filter with its O-ring in place. Note the orientation of the filter (open side faces outward).
    • Reinstall the cover and torque the bolts evenly — do not overtighten.
  • Reinstall the drain bolt
    • Screw in the drain plug with the new washer. Tighten securely but do not overtighten (spec in manual).
  • Refill with oil
    • Add 1.0 liter (1.06 US qts) of fresh 10W-40 oil through the filler hole. Use a funnel to avoid spills.
  • Check oil level
    • Start the engine and let it idle for about a minute, then shut it off and allow oil to settle for a minute.
    • With the bike upright and level, insert the dipstick (do not screw in), remove it, and check the oil level. Top off if necessary.
  • Reinstall skid plate
    • Bolt the skid plate back on with the three fasteners removed earlier.
  • Inspect for leaks and clean up
    • Check around the drain bolt, filter cover, and case for leaks. Wipe away any oil drips.

2009 Yamaha WR450F Specific Call-Outs

  • Drain plug location: On the lower right rear of crankcase, not at the very bottom.
  • Washer replacement: Always replace the copper sealing washer to prevent leaks, a common oversight that causes repeat jobs.
  • Oil capacity: For the 2009 model, about 1.0 liter (with filter change). Always double-check with the owner’s manual but avoid overfilling as this can harm the engine.
  • Oil check: Stand the bike upright and level when checking the dipstick. Tilting can give a false reading.
  • Oil and filter intervals: Yamaha recommends changing both every 1,000 km or as specified in your manual for racing/extreme use.
  • Skid plate fasteners: Older models might have 8mm bolts; others may have Allen heads or a mix, check before you start.

Final Pro Tips

  • Never reuse gaskets or washers when changing oil — new parts help prevent leaks.
  • Disposal: Take used oil and filters to a recycling center.
  • Check your manual for updated specs and torque values.
  • Keep a maintenance log to track oil changes and service intervals.

MotoSport.com is committed to helping you do the job right. Change your oil regularly and your 2009 Yamaha WR450F will reward you with years of reliable trail and track performance.

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Shop Oil Fillers and Drain Plugs for a 2009 Yamaha WR450F 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.