What Happens If Air Filter Is Dirty In Dirt Bike

man looking at dirt bike

A dirt bike filter prevents dirt, dust, and other unwanted particles from reaching your engine.

But when left unclean for too long, what happens if the air filter is dirty in your dirt bike? Can it seriously damage your bike?

A dirty air filter on a dirt bike can restrict airflow to the engine, resulting in decreased power and acceleration and an increased risk of engine damage. A dirty air filter also allows dirt and debris to enter the engine, leading to faster wear and tear on internal components.

What happens when if the air filter is dirty in your dirt bike?

When your dirt bike has a dirty air filter, the engine experiences difficulty when drawing air to provide power for your dirt bike.

The engine runs hot and becomes at risk of more severe damage. 

And with today’s air quality, you’ll need a proper air filter for your dirt bike more than ever to keep impurities out of your engine.

If left unclean for a long time, a dirty air filter can lead to major problems, such as:

  • Slower acceleration – A dirty air filter can lead to decreased power and slower acceleration, causing the dirt bike to feel sluggish and less responsive.
  • Higher fuel consumption – When the air filter is dirty, the engine struggles to draw the air it needs for its air-fuel mixture. As a result, it consumes more energy than usual (talk about burning cash).
  • Higher risk of engine wear – Because of the increased effort in producing power for your dirt bike, the engine tends to overheat, causing internal components to suffer increased wear and tear.

7 signs of a dirty dirt bike air filter

Luckily, it’s easy to figure out if your air filter is already dirty.

If you spot these 7 signs on your dirt bike’s air filter, it’s time for a cleanup or replacement:

1. Air filter looks physically dirty

A brand-new air filter looks almost like a perfect shade of white (or whatever color it is originally).

Over time, as contaminants pass through the filter, it turns into a darker shade of brown.

So if you want to see how your air filter is doing, this is the first sign you should look out for during your inspection.

Inspect the air filter under ample lighting to see if it’s in dire need of cleaning.

2. Higher fuel consumption

As I mentioned, a blocked air filter decreases oxygen flow in your engine.

So to compensate, the engine consumes more fuel to produce the power your dirt bike needs. 

So if you notice yourself loading up gas for your dirt bike more frequently, that could be a warning sign that your air filter needs to be cleaned. 

3. Decreased power

Have you experienced choppy acceleration on your dirt bike or found that you have to rev the throttle more than usual to achieve faster acceleration?

If yes, your engine may not be getting the right amount of air it needs to deliver the horsepower you want due to a clogged air filter.

4. Engine is difficult to start

Despite multiple attempts at kicking the kickstart lever and revving the engine, your dirt bike is refusing to start.

It takes several tries before the bike finally comes to life.

If this sounds like your case, your engine could have a low air-fuel ratio due to a dirty air filter. 

5. Engine light is on

A clogged air filter can allow contaminants to enter the engine, leading to carbon deposits that can trigger the engine light to signal a potential issue in the engine’s health.

Of course, an active engine light could mean plenty of things, but a dirty air filter can be one of the culprits behind this.

Try checking and cleaning your air filter first, and if the engine light stays on, you can bring your dirt bike to a mechanic.

6. Fuel smell

An unburnt fuel smell due to excess unburnt fuel can indicate a dirty air filter or something more serious, such as a fuel tank leak.

7. Blowing black smoke

Black smoke coming out of your dirt bike means there’s an issue with the fuel or oil on your dirt bike.

One of the main reasons for this is a dirty air filter, which causes your engine to run rich.

How often should you clean your dirt bike air filter?

There are several factors that determine how often you should clean your dirt bike air filter, including your dirt bike’s type, terrain you ride on, and how often you ride. 

If you often ride in dusty areas, or if you’ve been practicing your racing skills frequently, you’re likely to clean or replace your air filter after every ride.

To be on the safe side of caution, you can check your owner’s manual for instructions and recommendations for cleaning your air filter.

There are three types of air filters on the market, and they vary in how much cleaning they require:

Foam Filter
Image courtesy of mxstore.com.au
  • Foam air filters. These filters are the cheapest but get clogged up the fastest. 
Paper Filter
Image courtesy of AML on Amazon
  • Paper air filters. Paper air filters are the cheapest, but they clog up easily. They’re also irreplaceable.
Cotton Filter
  • Cotton gauze air filter. While they’re the most expensive, they’re also the most efficient air filter among the three. They can be cleaned after every ride and do not need to be replaced frequently.

How to clean your air filter

Cleaning your dirty air filter is easy.

Just follow these steps and make sure to use the proper cleaner for air filters:

1. Remove the air filter from your dirt bike. If it has a housing, grab your trusty screwdriver and set aside the screws and bolts securing the housing. You can place a cloth over the air box to prevent debris from falling into the air box.

2. To clean the filter, use a small brush and an appropriate cleaner, such as a filter cleaning solution specifically designed for air filters. This will help remove dirt and debris, including stubborn dirt.

3. When you’re confident that you’ve removed all dirt and debris from the filter, rinse it with clean water to remove the suds from the cleaning solution.

4. Let the filter air-dry before putting it back on your dirt bike, which may take several hours or even overnight.

4.5 For oiled filters, you’ll need to oil them after drying. Grab your air filter oil and spray it evenly on the filter’s pleats. Apply as many as possible or until all of the filter is lubricated. Allow the oil to wick for 20 minutes, then squeeze out any excess from the filter.

5. Once dried and oiled, you can put the air filter back and screw back the filter’s housing. 

Here’s a good walkthrough of how to clean and oil your dirt bike’s air filter:

Wrapping up

The air filter on a dirt bike is responsible for keeping the air in the air-fuel mixture pure and providing the power the bike needs.

A dirty air filter can lead to problems such as slower acceleration, higher fuel consumption, and increased engine wear. 

The air filter should be cleaned after every other ride or after any ride in dusty conditions or at high speeds.

To clean the air filter, remove it from the bike and scrub it with a cloth and a filter-cleaning solution. Let it dry completely and oil it if needed before replacing it.