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Best Air Filter Oil 2020

Air filter oil is used with certain performance air filters. The filters themselves are made from a foam type material that is soaked in the specially formulated air filter oil. The oil once applied, is very effective at keeping debris out of your engine. Good quality air filter oil keeps your engine components clean and functioning well. As a result, it decreases the amount of time that you need between dirt bike engine oil changes.

The filters can be cleaned and re-oiled after a certain amount of running time. Riding regularly in very sandy conditions may necessitate changing the filter after every ride. To clean your filter, use a filter specific solvent cleaner. Spray on or soak in the cleaner and leave for a while to let the cleaner start working.

Rinse in warm water and squeeze excess water out of it. Do not wring! Leave in the airing cupboard overnight or until completely dry. When dry, soak the filter in the filter oil evenly. Allow too dry before use.

Deciding what filter oil to use can be a challenge as most dirt bike manuals will not recommend a specific type. We have reviewed our favourite motorcycle air filter oils below. Keep reading for top 5 tips for air filter maintenance:

Top 4 Motocross Air Filter Oils 2020

1. Maxima Foam Filter Treatment

Maxima Foam Air Filter Oil

As with all of their products, Maxima created another highly effective oil that does an outstanding job. This Foam Filter Oil by Maxima took 3 years of dedicated research and development. It is a fully synthetic polymer formula that allows for between 4 and 13% more airflow while keeping up to 8 % more contaminants from entering through the air filter.

The oil has water and fuel repelling properties that keep the fluids from entering through the air filter. Off-road riders that often find themselves at river crossings or riding in the rain benefit hugely from using oil filter oil.

Air filters are very susceptible to chemical damage. This oil by Maxima test for resilience to chemicals and so their products will not cause damage to the make-up of the air filter. Using this product keeps your engine and engine oil cleaner than ever. 



  • Formula repels water and gas
  • Extremely well researched formula
  • Keeps engine oil clean and efficient




2. Bel-Ray Foam Filter Oil

Bel-Ray Dirt Bike Filter Oil 2020

Bel-Ray’s Foam Filter Oil is a popular choice among both professional racers and weekend riders alike. The formula has been proven to work time and again in virtually all situations.

Bel-Ray Foam Filter Oil is designed to work for street, off-road and high-performance racing applications. It can be safely used on any foam filter and does not corrode the filter itself, or it’s bond. Like all good quality foam filter oils, this one increases airflow through your air filter.

The oil itself has been formulated to be ultra-viscous which creates an oil barrier to capture micron-sized particles before they have the chance to enter through the air filter. Bel-Ray’s Foam Filter Oil is also waterproof, which prevents clogging in wet conditions.


  • Ultra-viscous formula
  • Waterproof to prevent clogging
  • Can be used in all riding conditions




3. Yamalube Air Filter Oil

Yamalube Foam filter oil for motocross

Yamalube by Yamaha has been credited with creating some of the best possible oils for your motorcycle. Their dirt bike air filter oil is no exception (also used as ATV filter oil).

Yamalube Foam Filter oil is a petroleum-based synthetic oil that will keep debris out of your engine as well as any other oil for air filters. Yamaha’s formula is designed to create a catch for unwanted dirt and dust, preventing it from entering into your bike’s engine through the intake tract. 

Like other foam filter oils, the Yamalube product will also prevent water from getting through your filter and into your engine. This is a high-quality oil manufactured by a company with many years of experience in the field. 

*Must be sourced outside of the UK.


  • Manufactured by Yamaha
  • Effectively filters out debris
  • Waterproof formula




4. Lucas Oil High-Performance Air Filter Oil

Lucas Oil Best Filter Oil

Lucas Oil is known for its innovation when it comes to manufacturing performance oils. 

Lucas’ High-Performance Foam Filter Oil has been formulated to have a slight tackiness to it. This ensures the oil will stay in place on the air filter and will increase the performance throughout the time between services. 

It is a low solvent, low viscosity oil that will easily penetrate the air filter to stop dust, dirt, and sand from entering your engine.

Like other high-quality filter oils, the Lucas Oil filter oil acts as a moisture barrier to prevent water and other fluids from being sucked in through your dirt bike intake tract. It is good for use in all temperatures and does not clog in cooler weather. 

The blue colour makes it easy to see when the filter is fully covered in oil. Lucas Oil products are used by the Troy Lee Designs team, so their performance is practically guaranteed. 

*Must be sourced outside of the UK.

Benefits of this air filter oil:

  • Works well in cold applications
  • Blue in colour
  • Tacky to help keep the oil in place




Can you clean an air filter?

The question as to whether you should clean an air filter is a hotly contested subject. It is good to bear in mind that air filters are not overly expensive, and engines are! If you damage your air filter whilst cleaning it, you run the risk of causing extensive damage to your engine! 

In competitions or extreme endurance races, where reliability is an absolute issue, you should never start out with an air filter which is not working fully. If you find yourself having to clean an air filter then you could follow these tips, however Motocross Advice are of the opinion that you should never clean an air filter unless absolutely necessary. ALWAYS replace it with a new one:


In an emergency:

  1. Remove the air filter and check for clogged, and overly blocked areas. Carefully remove debris and try to wipe away any wet or clumped dirt.
  2. Check the air box for loose debris or any clogged ports. Remove all debris.
  3. If you find any moisture, dry out the interior of the air box with a clean cloth.


Never put a wet air filter back into your bikes air box. Moisture can irreparably damage your dirt bikes engine.

If in doubt, always carry a spare air filter with you, rather than cleaning an existing filter.   

Here are our 5 top tips for maintaining your Air Filter:

    1. Clean your airbox regularly
    2. Spray the inside of your airbox with GT-85 to help catch dirt before it is filtered. This will also make your airbox easier to clean
    3. Clean and re-oil regularly to prevent premature engine wear
    4. Consider renewing filter after every ride in sandy conditions
    5. Never use petrol to clean your filter