For those looking to increase the power of their
motorcycle, replacing the stock air filter is usually a good
place to start. Many people say that aftermarket air filters
give you the best bang for your buck in terms of power gains.
It is also a very simple modification that does not require
much technical knowledge or skill with a wrench. Coupled with
an aftermarket exhaust and more aggressive carburetor jets,
an aftermarket motorcycle air filter will be especially effective.
Going back to the basics, increasing horsepower means increasing
the amount of oxygen and fuel getting to the engine. Aftermarket
motorcycle air filters are designed to allow air to pass through
with less restriction while still protecting the engine from
contaminants that could damage internal engine parts. Most
stock filters are made of paper and are disposable. The filter
is pleated to increase the surface area through which the
air can pass. The paper is good at filtering out even very
small particles but it can restrict air flow significantly.
Probably the most popular aftermarket air filter is made by
K&N. They offer quality filters that boost performance
while still meeting emissions requirements and protecting
the engine. They are probably less aggressive than some filters
but they find a good medium for someone who is looking for
something between an all out race bike and a bone stock ride.
These filters still have the same pleated design to maximize
surface area but K&N filters are made out of cotton sandwiched
between two layers of thin mesh. A tacky oil coats the cotton
of the filter element to trap any particles before they can
reach the engine. Though K&N air filters cost quite a
bit more than OEM paper filters, they can be cleaned and re-oiled
with a special renewing kit. Many even come with a million
mile warranty so you may even save money in the long run since
the filter itself will not have to be replaced. There are
a ton of knock-offs out there but I personally would rather
pay a little more and purchase a trusted name like K&N
than trust my engine to a nameless brand.
In cars, the whole air box can be replaced with a high flowing
tube but most aftermarket motorcycle air filters are direct
OEM replacements. This means to install it, you just have
to open up the air box, remove the old filter and pop the
new one in (Consult your owners manual if you need assistance
with that). This power mod is really too simple to even be
considered a true modification but it definitely is a good
place to start adding power to your motorcycle.