P70
HOW-TO
MUFFLER REPACKING
T
here are two good reasons to repack your
muffler. First, reducing the sound output of
your bike lessens the chances of other peo-
ple, especially non-motorcycle riders, complaining
about you riding. Second, and contrary to common
belief, a properly packed muffler increases the
power of your bike. In fact, it can add as much as
two horsepower. For both off-road and street mo-
torcycles, the fiberglass packing materials in your
muffler break down over time due to the extreme
heat inside the muffler. Allowing water to get inside
the muffler can accelerate the degradation process
so it is recommended that you use a plug in the
endcap when washing your bike. Most stock and
aftermarket mufflers are designed to replace the
packing material relatively easy and we will show
you the common steps here. If you prefer, some of
the aftermarket exhaust companies and local shops
offer rebuild services.
How do you know it is time to check your muffler
packing? Just like the internal parts in your motor,
if you have put 20-plus hours on your bike, or if you
think that water may have entered the muffler due to
riding in rain or mud, it is time to check the pack-
ing. Some indications that you are due for fresh
packing will be discoloration of the outside of the
HORSEPOWER!
QUIETLY
INCREASE
YOUR
This is an example of
some mildly used packing
materials and even this
shows signs of heat and
moisture damage.