The air filter: which is better?

In the world of races and competition, the air filter is just one more option, since it is often replaced by a trumpet or simply does not install.

In the “street” motorcycles the situation is very different, since one of the objectives of the owner is that the engine has a long duration and for this we need the air that enters the engine to free it from external particles that can deteriorate it.
Most of these particles that can damage an engine measure between 10 and 20 microns (a human hair has a diameter of 50 microns) and a good air filter can retain up to 97% of these particles.

The problem is that the more restrictive a less efficient air filter is, so you have to adopt different solutions as we will see below.

The filter also emits sound
More specifically admission. When the vacuum occurs in the cylinders because the pistons lower the air is forced to enter, emitting a characteristic sound.
The fact is that bikers normally appreciate the sound of the escape than that of admission, for this reason manufacturers concentrate their efforts on creating an admission as silent as possible to be able to grant these decibels "stolen" to escape, all within the maximum that the regulations have established. That is, a silenced air filter is needed so that the escapes can emit a stronger "standard" sound.
Therefore the original filters have extra layers of wave shock absorber tissues and filter boxes usually have the smallest openings than recommended, or with gates of the Harley-Davidson Active Admission type. All this allows the vehicle to comply with the regulations, but it remains power.
We reach the conclusion that replacing the origin filter with an air filter designed to be more efficient will allow the more air in the cylinders, increasing the power, the torque and the performance.

Types of filter
A good air filter is one that combines a good air flow with maximum particle retention.
You can measure both the ability to filter particles (Test SAE J726) and the air flow delivered a filter (Test Flowbench), to know its performance and efficiency.

In motorcycles there are 3 main types of air filter in relation to the material with which they are built:
-Paper: It is the most economical filter and is usually the equipment of origin in most manufacturers. It offers folded to have a greater filtering surface in lesser space and performs its work quite well.

This type of filter is progressively observed as particles are catching, so it must be regularly replaced.
-Espuma impregnada en aceite: Es uno de los diseños más eficientes a la hora de atrapar la suciedad, y casi no pierde eficiencia aunque esté sucio. The paste is that a fairly large size is needed to have good air flow, so they are usually spectacular. They are used mainly in offroad applications.

-Fibra de algodón impregnada en aceite: This type of filter element is what we usually find in high performance filters, K&N type, and combine the advantages of foam and paper filters.

It occupies little volume and cotton fibers are able to catch more particles than paper, and most importantly, these particles accumulate only on the filter surface, so they do not block air passage holes, obtaining and performance and performance and Optimal efficiency.

These filters have "regener" in each review (clean them and oil with a Specific kit) and can be reused about 25 times, that is, more than 200,000 km.

The best filter
Now that we know its functions and the different types of air filter we only have to choose which filter box we like most, since here there are many options and in this case the decision is usually aesthetic, since most filters of filters of High performance are able to offer more clean air than the engine may need at any time.

As always, it is only to remember that if we change the amount of air that enters the engine, you have to recalibrate (in the case of carburation) or Reprogram the switchboard (In the case of injection) so that the entire system works correctly and balanced.

Frank Burguera

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