AIR FILTER for Motorcycle, Maintenance and Advice

Air is one of the three essential elements to generate the explosion inside the cylinder which, in turn, generates the movement of the engine . The other two elements are the fuel and the spark , which gives it, in this case, the spark plug . The engine sucks all the air it can from the environment where it is working, so the air filter must allow as much air as possible to pass to the explosion chamber, but preventing impurities that travel suspended in it, especially dust , from passing . If on a road motorcycle it is key to have a good filter, in a mountain one it is vital, because it works immersed in dust and dirt.

In the event that an air filter becomes clogged due to dirt , the air flow that reaches the engine’s intake system would be significantly reduced , creating an imbalance in the optimum mixture of air and fuel that feeds the engine and in the one that has to have more gasoline than air. The lack of the latter would prevent the fuel from fully igniting during the combustion phase. The direct consequence would be the reduction of engine power. It would also slow throttle response and make the engine hotter than desired. If the air filter were to become completely clogged, the engine would be unable to ignite the fuel at all and would stall. We recommend that you know how a 4-stroke and 2-stroke engine works .

The air filter of a motorcycle is made up of a filter element that rests on a plastic, rubber or metal frame. The element itself can be made of a number of different materials: folded paper, cotton fiber, wire mesh, or foam. Let’s see them all:

Types of motorcycle air filters

#1 Foam Air Filter

The foam air filter is the most used on off road, although it is also mounted on some road motorcycles. It is made of foam or synthetic sponge, divided into several layers. This material must be impregnated with a specific oil , which is responsible for retaining airborne dust particles that have been trapped in the foam cells as the air passes through them. When the foam filter is very dirty, it must be cleaned with specific products and greased again so that it continues to fulfill its function, and reinstall it on the motorcycle.

#2 Paper Cartridge Air Filter

Many road bikes often use an accordion-shaped paper cartridge as an air filter. The main advantages of paper over foam are its price and the fact that they have a significantly higher useful filter surface, even if they are of the same size, thanks to the folding technique. The most notable downside they have is their maintenance. They cannot get wet, therefore, when they are dirty they can only be cleaned by blowing them with pressurized air, and it is not always easy to do so. Therefore, they must be replaced frequently.

#3 Textile air filter

Another option that the industry offers us is the washable textile air filter . It is made of layers of cotton gauze, four to six, placed between two aluminum meshes to which they are folded and oiled. It has a function similar to that of foam but a filtering capacity superior even to that of paper, which allows a greater entry of air into the intake flow with the result of an increase in acceleration and horsepower of the engine. In addition, they have almost identical maintenance to foam filters, so their useful life is much longer than other filters. According to K&N Filters, inventor of cotton filters, these have a useful life of about 50,000 miles between cleanings, depending on driving conditions. In many cases more than the life of the motorcycle itself.

Motorcycle air filter maintenance

Preventive care of the motorcycle air filter  should be a priority . Remember, this element is the only thing that stands between the sensitive parts of your motorcycle’s engine and a huge amount of dust and harmful agents that are in the air. Repairing premature cylinder, piston and ring wear is much more expensive and difficult than maintaining the air filter well . You should check the filter frequently using the periodic maintenance charts that all motorcycle manufacturers provide in their service manual. It details the maintenance proceduresto be performed and the specific mileage intervals. We may need to inspect and clean or replace the air filter more frequently if we have been traveling in extremely dusty or dirty conditions.

In most cases, the paper filter should be replaced as soon as dirt buildup is evident.. However, when there is only a little buildup, a good shake or a blast of air from the compressor can remedy the situation. Foam, mesh and cotton filters can be washed when convenient and re-greased for reuse, following the instructions provided by the filter manufacturer. The cleaning process can vary from brand to brand, but most require the use of a cleaning product, such as a specific degreaser, to remove old oil and dirt trapped in the filter. You have to be patient and allow enough time for the degreasing solution to do its job. Then it is convenient to rinse the filter thoroughly under the tap, with hot water if necessary, and let it dry. When the filter is dry, apply a generous layer of special filter oil, which retains dirt. Finally, it is advisable to inspect the mounting surfaces of the carburetor and filter, and clean them as well. In the event that you see that the clamp that fixes the filter is in poor condition, do not hesitate to change it.