Air Filter Cleaning – Replacement Guide for 2009 Yamaha TTR125

Shop parts for a 2009 Yamaha TTR125 Dirt Bike.

The air filter in your 2009 Yamaha TTR125 is crucial for maintaining optimal engine performance and protecting crucial components from dirt and debris. This model uses a foam air filter tucked behind the right side number plate and is especially exposed to dust and mud during trail rides. Cleaning – replacing it at regular intervals ensures a longer engine life and smoother throttle response.

Preparation

  • Work on a clean, stable surface with your bike securely parked.
  • Gather supplies: a bucket of warm soapy water, foam filter cleaning solution, air filter oil, latex gloves, and a clean rag.
  • Have a replacement filter handy if the existing one cannot be cleaned.

Removal

  1. On the right side of the TTR125, locate the side number plate. Unscrew the D-ring bolt by turning counter-clockwise, then remove the two rubber tabs by pulling them from their grommets.–
  2. Carefully remove the side plate. This will expose the air box cover.
  3. Unhook the quick release fastener – typically a rubber band or bungee – securing the air box cover.–
  4. Pull off the cover and carefully remove the foam air filter.

Cleaning

  1. Inspect the filter. If heavily deteriorated, replace – otherwise, proceed to clean.
  2. Submerge the foam filter in cleaning solution or warm soapy water. Squeeze – do not wring – to remove old oil and dirt.–
  3. Rinse multiple times until water runs clean. Never use heat to dry – let it air dry naturally.
  4. Once dry, pour air filter oil into a plastic bag and add the filter. Squeeze until thoroughly saturated, ensuring an even coating.–
  5. Apply lithium-based grease or a thin film of filter oil to the filter's sealing edges for maximum dust protection.

Replacement

  1. Install the clean or new filter into the air box, making sure it seats firmly against the rim.
  2. Reattach the air box cover and secure with the fastener.
  3. Replace the side number plate, securing all tabs and the D-ring bolt.
  4. Dispose of used cleaning chemicals – old filters in an environmentally responsible manner.

Maintenance Tips Specific to the 2009 Yamaha TTR125

  • This model's air box is designed for easy access, but the right side panel tabs can be stiff if not regularly cleaned. Use a small brush or compressed air to keep the mounting area free of debris.–
  • The TTR125LE (large wheel, electric start) shares this filter method, so steps apply across all 2009 TTR125 variants.–
  • It is recommended to check the air filter after every ride – more frequently if riding in wet or dusty conditions.–

Why Air Filter Care Matters

The 2009 TTR125 relies on a clean air filter for proper combustion and consistent power delivery. Engine wear accelerates rapidly when dirt bypasses a compromised filter. Following this MotoSport.com cleaning – replacement process ensures a dependable ride every time.

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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.