How to Change the Oil in a 2018 Kawasaki KLX140G

Shop parts for a 2018 Kawasaki KLX140G Dirt Bike.

Routine oil changes are essential for keeping your 2018 Kawasaki KLX140G dirt bike running smoothly and reliably. This guide, brought to you by MotoSport.com, walks you through a thorough, step-by-step oil change, along with the specific tools required and notable tips for this model.

Tools and Supplies Needed

  • Ratchet and extension
  • 8mm socket (optional for some bolts)
  • 17mm socket (for drain bolt)
  • Torque wrench
  • Drain pan
  • New crush washer (recommended)
  • Oil funnel
  • OEM oil filter (part no. 52010-1053)
  • Quality 10W-40 4-stroke motorcycle oil (You’ll need up to 1.2 quarts for KLX140G)
  • Clean rags or shop towels
  • Gloves (recommended for a cleaner job)

Preparation

  • Ensure the bike is on a level surface, ideally using a motorcycle stand for stability.
  • Gather all your tools and supplies so everything is within reach.
  • If the engine is cold, start the bike and let it idle for 1-2 minutes. Warm oil will drain more quickly and completely.

Step-By-Step Instructions

  1. Remove the Oil Dipstick
    • Unscrew and remove the oil dipstick from the right side of the engine. This vents the crankcase and helps oil drain faster.
  2. Position the Drain Pan
    • Place your drain pan directly under the drain bolt, which is located on the lower left side of the engine case.
  3. Remove the Drain Bolt
    • Using a ratchet and 17mm socket, carefully loosen and remove the drain bolt along with the crush washer. Allow all oil to drain out completely.
    • Inspect the crush washer and replace it if worn or damaged (prevents leaks).
  4. Remove the Oil Filter
    • The KLX140G uses a cartridge-style filter behind a cover secured with 8mm bolts.
    • Undo the bolts, remove the cover, and take out the old filter. Note the orientation of the filter for correct reinstallation.
    • Clean the cover and surrounding area with a rag.
  5. Install New Oil Filter
    • Lightly oil the O-ring of the new filter with fresh oil.
    • Insert the new filter in the same orientation as the old one. Refit the cover and tighten bolts to the specified torque (consult your owner’s manual; typically around 7 ft-lbs).
  6. Refit Drain Bolt
    • Reinstall the drain bolt with new or clean crush washer. Use a torque wrench to tighten the bolt to specification to avoid stripping threads (usually about 14.5 ft-lbs, but check your manual).
  7. Add Fresh Oil
    • Place a funnel in the dipstick hole and pour in 10W-40 4-stroke motorcycle oil. The KLX140G oil capacity with filter change is approximately 1.1 to 1.2 quarts (see your owner’s manual for exact spec).
    • Replace the dipstick, but do not screw it in, and check the oil level. Add oil if needed to reach the proper fill line.
  8. Start the Engine and Inspect
    • Start the engine and let it idle for 1-2 minutes. Check for leaks at the drain plug and oil filter cover.
    • Turn off the engine, let it sit for a minute, then recheck the oil level using the dipstick (KLX tip: check with the dipstick screwed all the way in for the KLX140G). Top off if necessary.
  9. Clean Up and Dispose of Oil Properly
    • Wipe any spilled oil off the bike and properly dispose of used oil and filter at a recycling facility or auto parts store.

Model-Specific Tips & Call-Outs for the 2018 KLX140G

  • The Kawasaki KLX140G (2017–2020) shares its basic engine, oil filter, and drain setup with other KLX140 variants. The process above applies directly.
  • Oil Filter Orientation: Make sure you note which way the filter goes in—installing it backward can starve your engine of oil.
  • Oil Capacity: KLX140G and KLX140L use about 1.1–1.2 quarts of oil with filter change. Avoid overfilling.
  • Dipstick Reading: Always check the oil level with the bike upright and the dipstick screwed fully in on this model.
  • Crush Washer Reuse: Always inspect (and ideally replace) the drain bolt crush washer to prevent leaks.
  • First Change Reminder: If this is your first service (break-in oil change), do it sooner (after the initial 1–3 hours) to flush out debris from engine break-in.

Final Thoughts

Keeping the oil fresh is the most cost-effective way to extend the life of your KLX140G engine. Stick to the regular maintenance schedule and always use high-quality motorcycle-specific oil and an OEM or equivalent filter. For OEM KLX140G parts, maintenance kits, and more expert dirt bike tips, visit MotoSport.com.

Related Shopping Categories

Shop Motor Oil for a 2018 Kawasaki KLX140G Dirt Bike.

Shop Oil Filters for a 2018 Kawasaki KLX140G Dirt Bike.

Shop Oil Drain Pans for a 2018 Kawasaki KLX140G Dirt Bike.

Shop Tools for a 2018 Kawasaki KLX140G Dirt Bike.

Shop Oil Fillers and Drain Plugs for a 2018 Kawasaki KLX140G 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.