Air Filters

A Breath of Fresh Air:
The Importance of a Clean Air Filter

The air filter may hide itself away under the seat, but it has one of the most vital jobs when it comes to motocross. Motocross riding creates a harsh environment of dust, dirt, sand, water and mud all of which can cause havoc if they find their way into a motorcycle engine.

What is an Air Filter?

Air gets sucked into the carb or injector through the air filter. This action traps airborne contaminants preventing them from causing damage to the rest of the engine.

Although it may alter a little from motorcycle to motorcycle, the air filter is a thick foam cover. The cover fits over a cage-shaped structure and attaches to the air boot. The air boot links to the engine's carb or injector. The assembly sits to the rear of the engine under the front of the seat.

Due to the harsh conditions, motocross air filters are oil-soaked to trap every last spec of dirt and grain of sand. The oil is vital to the process and does its job almost too well, which means the air filter becomes clogged and needs cleaning after every outing.

Neglecting your Motorcycle's Air Filter

Allow an air filter to get clogged full of dirt and it can cause two things to happen. Neither of which is good news as both can harm performance.

The first problem you will encounter occurs because the air filter becomes so congested that it restricts airflow. Reduced airflow can mean the engine will burn more fuel. This action can lead to the spark plug running too rich, which can overheat the engine. The engine may also feel sluggish, with poor throttle response and have difficulty starting.

The second problem arrives if you continue to ignore a blocked air filter and it begins to allow dirt and sand through. Even a small amount of grit can obstruct parts of the carb or injector, which affects the fuel/air mixture

If only a few grains of sand get into the cylinder head, they can destroy the valve seats. At which point, the cylinder head is in a whole world of trouble.

How to Look After your Motorcycle's Air Filter

Before removing the air filter, make sure the area around it is free from dirt. When this task is complete, remove the foam element and submerge it in a bucket of cleaning fluid. Once the old oil and dirt are gone, gently squeeze out the foam without twisting or wring, which may tear the foam.

Using some dishwashing liquid, rinse the filter in warm water, squeeze and leave to dry. Before going on to the next stage, check the foam for tears or holes and if you discover any, throw the filter away.

Once the foam is completely dry, re-oil it by either using spray oil or, better still, by submerging it in a bucket of oil. The cleaned and re-lubed air filter is now ready to reinstall.

Hints and Tips for Air Filter Cleaning

The cleaning, rinsing and re-oiling process may sound laborious, however several things can make the job a lot easier. The first thing is to check out 24MX's Air Filter page. This section offers an impressive selection of products from the biggest names in the industry, including air filter cleaning products.

You can choose from a complete kit that may even include the buckets to submerge your air filter. You will also find items such as dirt removing liquids, filter oils and buckets, listed individually.

It's a rookie mistake to let the air filter get clogged. Experienced motocross riders know how important this job is and how to make life a lot easier.

Even top-quality air filters are quite inexpensive, so many riders keep a few spares. Doing this enables them to replace a dirty filter with a clean one allowing them to wash the old one later.

Last but not least, when completing these tasks, it is advisable to wear nitrile gloves to protect your hands from cleaning chemicals and oil. Nitrile gloves can be found on the ‘Cleaning and Maintenance’ page of the 24MX ‘Oil and Lubricants’ section.