How to Change the Oil in a 2021 Sherco 300SEF-R

Shop parts for your ride now.

Changing the oil on your 2021 Sherco 300SEF-R ensures optimal performance, increases engine life, and protects your investment—especially when riding in extreme conditions. This proprietary MotoSport.com how-to guide gives you every detail required for a professional oil change specifically tailored to this model.

Tools and Materials Needed

  • Socket set: 8mm, 17mm, and 4mm Allen head socket
  • Oil drain pan
  • New oil filter (specific for Sherco 300SEF-R)
  • Replacement O-rings (for oil filter cap and drain plug)
  • New copper or aluminum crush washers (for drain plugs)
  • Clean rags
  • SAE 10W60 motorcycle oil (0.9L)
  • Funnel (optional, but helps avoid spills)
  • Gloves (personal preference)
  • Torque wrench (to ensure bolts are tightened to spec)

Pre-Change Preparation

  • Warm the engine for a few minutes to thin the oil, making it easier to drain and more effective at flushing out contaminants.
  • Turn off the engine and place the bike on a stand so it remains upright and stable throughout the process.

Step-by-Step Oil Change Instructions

  1. Remove the engine guard:
    Some models have a skid plate, which should be carefully removed for access to the drain plugs.
  2. Locate and remove both drain plugs:
    The 2021 300SEF-R features two oil drain plugs underneath the engine, one of which is a magnetic plug.
    • Use a 17mm socket for the main drain plug (M19; torque spec: 22 Nm for reinstallation).
    • Use a 12mm socket for the magnetic drain plug (M12; torque spec: 15 Nm for reinstallation).
    Note: Both plugs have crush washers that must be replaced to ensure a proper seal and avoid leaks.
    Model-Specific Tip: The presence of two drain bolts ensures more complete draining—do not skip either plug.
    Let the oil fully drain. Allow several minutes for all the oil to leave the engine.
  3. Remove the pre-filter and oil filter:
    • Remove the small Allen bolts (typically 8mm or 4mm Allen) securing the oil filter cover.
    • Take out the oil filter—note its orientation for installation of the new filter.
    • Extract the mesh pre-filter for inspection and cleaning.
    Replace the oil filter with a new one at every change, as recommended by Sherco.
    Inspect and clean the mesh pre-filter if necessary.
  4. Install new filter, pre-filter, and replace seals:
    • Lubricate the new oil filter’s rubber seal with a bit of fresh oil before installation.
    • Insert the filter in the correct orientation.
    • Install a new O-ring with the oil filter cap, and replace crush washers/gaskets on the drain plugs.
    • Reinstall the oil filter cap (Torque: 15 Nm).
    • Reinstall the pre-filter and any caps or plugs associated with it.
  5. Reinstall drain plugs:
    • Tighten both plugs to the recommended torque specs: 22 Nm for the main drain (M19) and 15 Nm for the magnetic plug (M12).
  6. Refill with fresh oil:
    • Remove the engine oil filler cap.
    • Pour in 0.9L of SAE 10W60 four-stroke motorcycle oil.
    Use a funnel to prevent spills.
    Model-Specific Call-Out: This capacity (0.9L) is for the 300SEF-R—do not overfill.
    Check the oil level in the sight glass on the engine case. Once the bike is upright, the oil should be visible between the minimum and maximum marks.
  7. Final checks and start-up:
    • Reinstall the oil filler cap and engine guard/skid plate if removed.
    • Start the engine and let it idle for 1–2 minutes. Watch for leaks at all bolts, the filter cover, and around the case.
    • Turn off the bike and allow it to sit for a minute; re-check the oil level and top off if necessary.
  8. Dispose of oil and filter responsibly:
    • Used oil, filters, and rags should be taken to a recycling or hazardous waste collection facility—never pour oil down any drain or onto the ground.

Special Notes and Model-Specific Tips

  • Both 2021 Sherco 300SEF-R Racing and Factory models use the same oil change procedure, oil specs, and torque values. Do not skip removal of either drain plug for a complete drain.
  • Always replace both gaskets/crush washers and O-rings to minimize chances of oil leaks—reusing old seals can cause problems.
  • Use only motorcycle-specific full synthetic 10W60 oil—car engine oils may damage clutch or gearbox components.

Torque Specifications Recap

  • Main drain plug (M19): 22 Nm
  • Magnetic drain plug (M12): 15 Nm
  • Oil filter cap: 15 Nm

Conclusion

Perform this service at regular intervals (50–100 hours, depending on riding conditions) to maintain your Sherco 300SEF-R in peak condition and protect your engine for years of rides ahead. Always consult your owner’s manual for updates or region-specific details.

Changing oil as per the manufacturer’s recommendation is vital for longevity. Use proper tools and never rush the process for best results.
- MotoSport.com Tech Shop

Related Shopping Categories

Shop Motor Oil for a 2021 Sherco 300SEF-R Dirt Bike.

Shop Oil Filters for a 2021 Sherco 300SEF-R Dirt Bike.

Shop Oil Drain Pans for a 2021 Sherco 300SEF-R Dirt Bike.

Shop Tools for a 2021 Sherco 300SEF-R Dirt Bike.

Shop Oil Fillers and Drain Plugs for a 2021 Sherco 300SEF-R 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.