Air Filter Cleaning & Replacement Guide for 2018 Honda CRF250R

Shop parts for a 2018 Honda CRF250R Dirt Bike.

Your 2018 Honda CRF250R’s air filter is essential for optimal engine performance and longevity. This guide, crafted by MotoSport, gives you robust instructions tailored specifically for your bike’s dual-layer foam filter design and Honda’s unique airbox configuration.

Why Air Filter Care Matters for the 2018 CRF250R

  • Protection: The CRF250R comes stock with a dual-stage foam air filter engineered to trap airborne dirt, grime, and sand before they reach your engine. The outer coarse open-pore layer catches larger particles, while the fine inner layer ensures only clean air reaches the intake.
  • Performance: Clean filters allow for maximum airflow, ensuring the CRF250R’s potent engine gets the oxygen needed for high output. A clogged filter restricts power and risks engine damage.

Removal: Accessing the Air Filter

  1. Remove the seat by loosening the bolts on each side and sliding the seat back to access the airbox.
  2. Unscrew the wing nut or spring holding the air filter and carefully separate the filter from the cage–note the orientation for proper reinstallation.

Cleaning Process

  1. Inspect: Check the air filter for tears or damage. Replace if needed, as even small holes risk severe engine damage.
  2. Wash: Rinse off excess dirt. Submerge the filter in a container of air filter cleaner or mild detergent and gently squeeze (never wring or twist) to remove deep debris.
  3. Rinse: Rinse thoroughly with clean water, again gently squeezing out all cleaner and contaminants.
  4. Dry: Allow the filter to air dry completely out of direct sunlight.

Oiling and Reinstallation

  1. Oil: Use foam-specific air filter oil, as recommended by Honda. Evenly saturate the filter and gently work the oil through for full coverage–don't leave dry spots. Let excess oil drip off before installation.
  2. Grease the Flange: Apply waterproof grease to the sealing edge of the filter to prevent fine dust entry between the filter and airbox.
  3. Reinstall: Place the filter back on the cage, secure it with the wing nut, and ensure a tight seal. Reinstall the seat.

Replacement Guidelines & Tips

  • Frequency: Clean after each ride in dusty or sandy conditions, or at minimum every two to three rides in mild conditions.
  • Replacement: A worn, torn, or permanently stained filter should be replaced immediately with a model-specific foam filter.
  • Notable for 2018 CRF250R: The 2018 model's unique dual-stage foam design (as supplied by OEMs such as Twin Air and Putoline) is built for both high-dust protection and unrestricted airflow. Always use high-quality, dual-layer foam for best results.

Care Tips Specific to the 2018 CRF250R

  • Always check the filter cage for damage or cracks–replace as needed.
  • Double-check filter seating to avoid air leaks; improper sealing is a common cause of engine wear on this model.
  • Use only foam air filter oil designed for off-road motorcycles–avoid automotive or spray lubricants.

With proper care and timely replacement, your CRF250R's air filter will keep your engine running stronger for longer.

Related Shopping Categories

Shop Air Filters for a 2018 Honda CRF250R Dirt Bike.

Shop Air Filter Oil for a 2018 Honda CRF250R Dirt Bike.

Shop Air Box Covers for a 2018 Honda CRF250R Dirt Bike.

Shop Tools for a 2018 Honda CRF250R Dirt Bike.

Shop Intake Parts for a 2018 Honda CRF250R 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.