Cleaning and oiling your air filter in your motorcycle, ATV or UTV is one of the most important things you can do in regards to maintenance. If a filter isn’t cleaned and oiled properly, particles like dust, sand or dirt will get in and wear out your engine components a lot faster. With a properly cleaned filter, your machine is going to run a lot better, and it’s going to last a lot longer.

There are two major types of filters used by powersport vehicles: foam and K&N (pleated cotton). We’ve included instructions for both types – just pick your type below to get started. When you’re ready to clean and oil your own air filter, be sure to check out Rocky Mountain ATV/MC for everything you need.

How to Clean and Oil a Foam Air Filter

What You Need to Begin


Tusk Deep Socket T-Handle Wrench
Pro Guard Disposable Powder Free Nitrile Gloves Service Manuals
Tools to Access Air Filter Rubber Gloves Service Manual
Bike Master Micro Fiber Towel Maxima Contact Cleaner Maxima Air Filter Cleaner
Clean Cloth Contact Cleaner (or WD-40) Air Filter Cleaner
Twin Air Liquid Dirt Remover Cleaning Tub Twin Air Liquid Power Oiling Tub Maxima Foam Air Filter Oil
Cleaner Soaking Tub / Bucket Oil Tub / Bucket Air Filter Oil
Maxima Hi-Temp Waterproof Grease
Grease

Instructions

1. Carefully remove the air filter.

Removing the Air Filter

Watch in the Video

First, you’ll need to access the air filter. It varies from vehicle to vehicle, so check your service manual if you aren’t sure how to remove it on your machine. We used a 2004 YZ250 for our video, and we had to remove the seat to get at the air filter.

Carefully remove the air filter. Take the bolt out and pull the filter away from the cage. Air filters are messy when you take them out and when you put them back in. When you’re pulling out your air filter, be careful not to drop dirt off of your air filter into the air boot.

2. Ensure the air boot is clean.

Cleaning the Air Boot

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Even if you’re careful, there’s a good chance some dirt could fall into the air boot. It’s always a good idea to inspect the air boot. Clean any dirt that may have fallen in there. Spray the air boot with some contact cleaner or WD-40. With a clean rag, carefully wipe it out.

It’s also possible that some dust or dirt got in your air boot during your last ride, and checking it out can give you a good indication of how well you’re cleaning and oiling your air filter.

3. Let the air filter soak in cleaner; then squeeze it out.

Soaking the Filter in Cleaner

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There are several different brands and types of filter cleaner and oil, so it’s important to always read the instructions on the label. We use a petroleum-based product for this tutorial, but some are biodegradable and require a different procedure. Regardless of what you use, make sure you’re following the guidelines recommended by the manufacturer.

There are many different types of solvents used to clean air filters. Some people use automotive solvents or kerosene. We recommend cleaners that are made by the same manufacturers that make the filter oil. They do a great job, and they’re safe. Some people use gasoline. We recommend against this as it can be dangerous, and it can actually damage foam air filters.

We recommend completely submerging the filter in the cleaner. This allows you to really get the dirt out. Place about a gallon of cleaner into a tub or bucket. We use the Twin Air Liquid Dirt Remover Cleaning Tub because it is strong and has a lid that seals tightly, preventing any of the cleaner from evaporating. It also has a tray that keeps the filter above the dirt that falls to the bottom.

Fill the tub up with about a gallon of cleaner. Throw in the dirty filter. Let it soak for a couple of minutes. Afterwards, squeeze it a little bit to help get some of the cleaner out of the foam. Do not wring or twist the filter as it can cause damage to the foam. Rinse the filter in the cleaner until it looks clean.

4. Wash and rinse the filter.

Washing the Filter

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You need to wash out the cleaner from the filter. If you use an automotive solvent or kerosene, wash the filter with dish soap in warm water. Otherwise, it could break down the oil when you apply it. Once it is clean, give it a quick rinse.

5. Inspect the filter for holes.

Inspecting the Filter

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Now that the filter is clean, it’s a good idea to inspect the filter – especially all of the glued seams. Make sure the filter is holding together and that it’s safe to put back into your machine. Check for any cuts or tears.

6. Apply oil to the filter once it is dry.

Saturating the Filter with Oil

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Let the filter dry. Then you can apply oil to it. There are lots of ways to oil a foam air filter. You can use an aerosol spray to get oil all over the filter and then work it in. You can drizzle oil on the filter like you would syrup over pancakes. We recommend submerging the filter in oil. This is a foolproof way of getting the filter completely covered with oil. We like to use the Twin Air Liquid Power Oiling Tub to hold the oil. Just like the cleaning tub, it is strong and has a lid.

Once the filter is completely soaked, squeeze out the excess. Remember not to wring or twist the filter. Once you squeeze out all the excess oil, massage the filter, ensuring that the remaining oil is evenly spread throughout it.

7. Clean the filter cage.

Cleaning the Filter Cage

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If necessary, spray a little contact cleaner on the filter cage, and wipe off any dirty spots that you can see.

8. Install the cage back in the filter.

Installing the Cage in the Filter

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Put the cage back into the filter, lining it up with the alignment tab and pushing the top through the hole.

9. Apply grease to the air filter to ensure a good seal.

Applying Grease to the Seal

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On most modern bikes, the air filter will seal just fine. However, as an extra precaution, we like to put a little grease on the rim as well. You can use a bearing or all-purpose grease. This just ensures that the filter will seal nicely against the surface of the air boot.

10. Reinstall the filter.

Reinstalling the Filter

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Carefully hold the filter on the cage, and put it into the air box. Watch to make sure that everything lines up right and that the filter is sealing up against the plate properly. Tighten the wingnut. You might want to run your fingers around the perimeter of the filter just to make sure that it hasn’t come off the cage and that it is sealed.

Be sure to put your lids back on the cleaning and oiling tubs. Put them away for the next time you clean your filter.

How to Clean and Oil a K&N Air Filter

What You Need to Begin

Tusk Deep Socket T-Handle Wrench Pro Guard Disposable Powder Free Nitrile Gloves Service Manuals
Tools to Access Air Filter Rubber Gloves Service Manual
Bike Master Micro Fiber Towel K&N Power Kleen Air Filter Cleaner K&N Air Filter Oil
Clean Cloth Air Filter Cleaner Air Filter Oil
Outerwears Pre-Filter
Pre-Filter (Optional)

Instructions

1. Carefully remove the air filter.

Removing the Air Filter

Watch in the Video

The first thing you need to do to maintain your K&N air filter is to remove it from the machine. It varies from vehicle to vehicle, so check your service manual if you aren’t sure how to remove it on your machine. In our video, we demonstrated on a Yamaha Rhino. For this machine, all we had to do was pull it up from the back and slide it out.

2. Ensure the air boot is clean.

Cleaning the Air Boot

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When you’re removing the filter, make sure you don’t knock any dirt into the air boot. On some machines – such as the Yamaha Rhino we used in our video – it might be pretty hard to do because of its upright positioning. However, on other machines, it can happen more easily. Always inspect the air boot and wipe it out if you need to. Just make sure it’s clean before the filter goes back on.

3. Apply the air filter cleaner to the filter. Let it sit for about 10 minutes.

Spraying the Air Filter Cleaner

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There are two things you need in order to properly care for your K&N air filter: cleaner and oil. K&N sells both in different sizes, including a convenient Recharger Kit that comes with the cleaner and oil in one package. Keep in mind that the oil comes in two types: an aerosol type that you just spray on and a bottle of oil that you can carefully drip on the pleats of the filter. We also sell other brands of cleaner and oil. Ultimately, it just comes down to which brand preference you have.

To clean the filter, you need to totally saturate the filter with the cleaner. Spray the cleaner on all over. It’s important that you don’t let the cleaner dry, so make sure to put plenty of cleaner on the filter. Once you’ve completely sprayed the cleaner on the filter, you can set it down and let it sit for about 10 minutes.

4. Rinse the filter from the inside out.

Rinsing the Air Filter

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Once the filter has sat with the cleaner for about 10 minutes, it’s time to rinse out the filter. It’s important that you rinse the filter from the inside out. If you rinse it outside in, you’ll push the dirt further into the fibers of the filter. Continue to rinse it until all of the dirt and oil come out of the filter. If all of the dirt and oil don’t come out, go ahead and reapply the cleaner.

5. Let the filter dry.

Setting the Air Filter Down to Dry

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Once the filter has been completely rinsed and the dirt and oil are out, you can shake the filter to help get some of the water out of it. At that point, simply set it aside and let it dry naturally. The filter has to be totally dry before you put the oil on.

6. Inspect the filter for holes.

Inspecting the Air Filter for Holes

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It’s always a good idea to inspect the air filter before you apply oil to it. Make sure it doesn’t have any holes or anything that would let dirt through.

7. Apply oil to the filter. Let it sit for about 20 minutes.

Applying Oil to the Filter

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If you use the squeeze bottle oil, apply it to the top of the pleats. The oil will slowly wick in to the fibers of the filter. The aerosol oil is easier to apply, and you can be more confident that you’re getting oil everywhere on the filter. For these reasons, we prefer the aerosol oil. Hold the can about three inches away from the filter as you spray it on. If there are any light spots, just touch them up by spraying them. Once the filter has been completely covered in oil, let it sit for about 20 minutes before you put it back in your machine. This will allow the oil to completely wick into the fibers of the filter.

8. Inspect the filter for complete oil coverage.

Inspecting the Oil on the Filter

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Once the filter has sat for about 20 minutes, give it a quick inspection to make sure that the oil coverage is good. If you see any light spots, hit them with the oil again. If it looks good, you can install it in your machine.

9. Install a pre-filter (optional).

Installing a Pre-Filter

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If you’re going to be riding in really dusty or sandy conditions, an Outerwears Pre-Filter is a good idea. They extend the life of the filter and maintain airflow. You simply slide it over your filter. Don’t oil it; install it dry.

10. Reinstall the air filter.

Reinstalling the Air Filter

Watch in the Video

Put the filter back in the machine, reversing the process you used to take it out. With the filter installed, it’s always a good idea to double-check the seal against the air boot to make sure it’s sealing properly. That way, no dirt or debris can get past the filter.

Cleaning your air filter is an essential part of machine maintenance. The best part is that it’s something you can do easily, and it can really extend the life of your machine. If you’re ready to get started, be sure to head to Rocky Mountain ATV/MC for all of your air filter needs.