Ultimate Guide to Dirt Bike Air Filters

Ultimate Guide to Dirt Bike Air Filters main image


Air filters are a simple component on a dirt bike, yet they play an incredibly important role in ensuring your bike not only runs correctly, but also ensures it doesn't come to a grinding halt. 

In this ultimate guide, we cover the ins and outs to dirt bike air filters!

What does an air filter do?

The lifeblood of any internal combustion engine is a mixture of fuel and oxygen, as a fire needs air to burn bright, so with a dirty filter your bike simply won’t run as it should. Now for an engine working in an environment which is trying to breathe through a constant barrage of flying dirt, mud, dust and for trail riders out there, seeds from plants and whatever else you happen to ride through, you have to take a moment to realise there is only one small piece of foam protecting the delicate heart of your engine from all of those potentially catastrophic particles.

What happens if I don't maintain my air filter?

It's incredibly important to maintain your dirt bike air filter, as even the smallest bit of dust could be catastrophic for your engine. Taking the five to 10 minutes to properly clean and oil your filter is a small price to pay compared to a spec of dust destroying your engine, which is bound to cost you thousands of dollars to repair.

How often should I maintain my dirt bike air filter?

We recommend maintaining your air filter after every day you ride, even if it isn't particularly dirty. If you haven't noticed, the air filter is a simple component that plays such an important role on a motocross or enduro bike, and neglecting it can have severe consequences. That's why it's incredibly important to start every day of riding with a freshly oiled air filter, and on days that are super dusty, even replacing it throughout the day is recommended. Having a spare air filter that's been pre-oiled at the track is advised in case you face some nasty conditions. You can learn how to maintain your air filter here: How to Change and Clean Your Dirt Bike Air Filter

What should I replace my old air filter with?

Majority of dirt bikes use a foam air filter that is reusable, and an aftermarket filter is likely one of the first things you'll need for your dirt bike. The standard OEM units are generally made of a single-layer foam and don't provide the level of protection of an aftermarket filter. Leading air filter brands such as Uni Filter, Motorex, Twin Air, and Funnelweb, all make their filters with dual-stage foam - this ensures your engine is being protected in the best possible way, while still receiving enough airflow. Air filters are also made specifically for each dirt bike model, so ensure your filter matches the manufacturer, model, and year of your bike. Using a filter from a different model could allow dirt to be sucked into the engine, causing a catastrophic mechanical failure. Learn more about which dirt bike filter to buy here: MXstore Air Filter Buying Guide

Are there different types of air filters available?

There are three main types of air filters being paper, cotton and foam, with the majority of dirt bikes using foam filters. There are a number of different foam filter types available, as each brand has their own special performance air filter features, such as the popular Twin-Air filters that boast a multi-layer foam filtration, to the Funnelweb filter that uses a uniquely cut profile to trap dirt and dust on the outside. Some companies also make air filter skins, which act as breathable overalls for your air filter - they're designed for super sandy or dusty conditions, and in the case of the Twin Air offering, it stops 90 percent of dirt and dust from getting through. Learn more about dirt bike filter types here: MXstore Air Filter Buying Guide

What do I need to maintain my air filter?

When it comes to maintaining your air filter, there are a bunch products you'll need to have handy, including an air filter cleaner and air filter oil. These two items should always be in stock in your shed or garage, as you're going to have to be reaching for them after and before every ride. It's also a really good idea to have spare filters and disposable gloves (more on that below). Learn how to maintain your dirt bike air filter here: How to Change and Clean Your Dirt Bike Air Filter


How do I maintain my air filter?

Maintaining your dirt bike foam air filter can be broken down into three different sections: cleaning, oiling, and installation. Cleaning your air filter consists of removing the dirty from your bike and using an air filter specific cleaner. Once the filter is cleaned inside and out, and it's incredibly important for the filter to completely dry before moving onto the next step, which is oiling the filter. The first step in applying foam filter oil is ensuring a no dirt particles are still in the filter, so this meaning hitting the filter against your hand to ensure even the tiniest bits of dirt are out. Once you're confident there's no specs of dirt in the filter, start to apply 'dots' of oil around the filter and massage the oil in until the filter is completely covered in oil. The final step is installation - firstly, check the air boot for any dust or dirt before applying the filter to the filter cage, and then carefully insert the filter into the air box - this is where having a clean air box comes in handy. Once the filter is secure, run your hands around the filter to ensure it's completely sealed. It should be noted some people like to apply a thin film of grease to the filter to help with sealing to the air boot. For a step by step process on maintaining your dirt bike air filter, click here: How To Clean and Change Your Dirt Bike Air Filter


5 Dirt bike air filter hacks and tips:

1. Use an air compressor:

If you have an air compressor handy, a super beneficial tip is to use it to blow any dirt that's still stuck in the foam air filter after you've cleaned and dried it. Typically, there will be a few grains still in the filter, and if they aren't blown out, your engine could potentially suck it up through the airbox and cause serious damage.

2. Bang out any dirt:

If you don't have an air compressor, then this tip is super important, while it's still something you should do even if you do the above tip. You'll want to hit the filter against your palm to bang out any stuck dirt. Do this process a number of times while moving the filter around - this accompanied by an air compressor will give you a completely dirt-free air filter.

3. Use an air box wash cover:

One of the best hacks for air filter maintenance is using an air box wash cover, which seals the air boot from an water and dirt and allows you to thoroughly clean out the air box. If you're planning to put your bike in storage, you can also use a wash cover box rather than an oiled filter, as the filter will need to be changed regardless before bringing your bike back into service.

4. Use gloves:

A box of disposable gloves is a requirement for any dirt bike rider, and they particularly come in handy for oiling air filters. Of course, you can always just clean the oil off, but we all know that is just seems to stick to our hands, no matter how much soap we use. A pair of disposable gloves make the job just a little cleaner and easier.

5. Own multiple filters:

Owning multiple air filters is recommended for every off-road motorcycle rider, and it's a brilliant hack for streamlining the maintenance process. By having spare filters, it means you don't need to wait for your recently washed filter to dry, which is super handy on back-to-back days of riding. Also having a spare filter handy while at the track that is pre-oiled is super beneficial, and can be life-save if you encounter some nasty conditions that require a filter change before the day is over.

Comments (1)

KTM 690 Enduro R

Do you have a better option for the KTM 690 air filter system.

Douglas Thomson on 5 September 2021
Hi Douglas, If you would like to reach out to our Customer Service Crew with the year of your 690, we can have a look at some options for you: https://www.mxstore.com.au/contact-us/ :) We look forward to hearing from you legend!
MXstore Response

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