How to change the oil in a 2021 Yamaha PW50 Dirt Bike

How to Change the Oil in a 2021 Yamaha PW50: Step-by-Step Guide

Shop parts for a 2021 Yamaha PW50 Dirt Bike.

Your 2021 Yamaha PW50 relies on fresh transmission oil for smooth performance and longevity. This guide, brought to you by MotoSport.com, outlines the full process for changing the oil and includes essential tips specific to the PW50.

Tools & Supplies Needed:

• 12mm socket or wrench (for drain bolt)
• Drain pan
• Measuring cup (for precise oil refill)
• Funnel
• Replacement transmission oil (see below for spec)
• New crush washer/gasket (replace every oil change)
• Rags (for cleanup)
• Gloves (optional, for cleanliness)
• Torque wrench (for correct bolt torque)

Which Oil to Use & How Much?

• Type: Use oil recommended on page 9-1 of the Yamaha PW50 manual (typically a 10W-30 or SAE 10W-30 for transmission oil – always double-check your own manual for exact specification).
• Quantity: 0.30 L (0.32 US qt, 0.26 Imp. qt)

Oil Change Interval:

• New bikes: After the first month, then again at six months
• Regular maintenance: Once a year for standard use

Step-by-Step Instructions

• Warm Up (Optional but Recommended):
  • Start and run the bike for a couple of minutes. This heats the oil, allowing it to drain more thoroughly.
• Stabilize the Bike:
  • Set the PW50 on its centerstand – this keeps the bike level for a proper drain and refill.
• Position Your Tools:
  • Place an oil drain pan directly under the transmission drain bolt (located underneath the engine).
• Remove the Filler Cap:
  • Unscrew the transmission oil filler cap on the right side of the engine. This allows air in so oil drains faster.
• Drain Old Oil:
  • Use your 12mm socket or wrench to remove the transmission drain bolt underneath the engine. Allow all the old oil to drain into the pan.
  • Check and replace the crush washer/gasket on the drain bolt. Always use a new washer to prevent leaks.
• Inspect & Clean:
  • Wipe any debris from the drain and filler areas. Clean the drain plug before reinstallation.
• Reinstall the Drain Bolt:
  • Screw the drain bolt back in by hand, then tighten to 14 Nm (10 ft·lbf) using your torque wrench.
• Refill with New Oil:
  • Set your measuring cup to 0.30 L (0.32 US qt) of fresh recommended transmission oil.
  • Place a funnel in the filler opening and pour the oil in slowly.
• Replace the Filler Cap:
  • Reinstall and tighten the oil filler cap.
• Cleanup & Final Checks:
  • Wipe any excess oil from around the engine.
  • Double-check for oil leaks around the drain bolt and filler cap.
  • Start the engine and let it run for a moment, then shut it off.
  • Check again for leaks and top off if the level looks slightly low.

Special PW50 Tips & Call-Outs

• Caution: Unlike traditional four-stroke engines, the PW50’s engine is a two-stroke, so you are only changing the transmission oil—not the actual engine oil. The engine itself is lubricated by the oil injected from the separate autolube system, which you should top off and inspect during regular maintenance.
• General Safety: Always check for oil leaks after each change and before each ride. If you see any leaks, have the bike inspected by a Yamaha-certified mechanic before further use.
• Interval Specific to Year/Model: The oil change process and specs are the same for all model years of the PW50, including the 2021. No special tools or techniques unique to this year are required, but always use a new washer each time you perform an oil change.
• Don’t Overfill: Too much oil can cause performance issues and leaks. Stick to the prescribed quantity for best results.

When to Replace the Gasket

• The drain bolt washer (crush washer/gasket) should be replaced with every oil change to avoid leaks.

Troubleshooting & Extra Maintenance

• If you notice milky, foamy, or foul-smelling oil when draining, the transmission may have water contamination or another internal issue—consult a Yamaha professional.
• Check the transmission area for worn or damaged seals if you spot persistent leakage.

Regular transmission oil changes are quick, easy, and one of the best ways to keep your 2021 Yamaha PW50 running strong for years of reliable fun. For genuine parts, tools, and more expert maintenance advice, trust MotoSport.com.

Related Shopping Categories

Shop Motor Oil for a 2021 Yamaha PW50 Dirt Bike.

Shop Oil Filters for a 2021 Yamaha PW50 Dirt Bike.

Shop Oil Drain Pans for a 2021 Yamaha PW50 Dirt Bike.

Shop Tools for a 2021 Yamaha PW50 Dirt Bike.

Shop Oil Fillers and Drain Plugs for a 2021 Yamaha PW50 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.