Catalytic Silencer - APRILIA RS 125 - 1996 Manual

CATALYTIC SILENCER

a
Avoid parking the vehicle catalytic ver-
sion near dry brush wood or in places
easily accessible to children, as the cata-
lytic silencer becomes extremely hot during use;
be very careful and avoid any kind of contact be-
fore it has completely cooled down.
The catalytic vehicle is fitted with a silencer with met-
al catalytic converter of the "platinum-rhodium biva-
lent" type.
This device provides for the oxidation of the CO (car-
bonic oxide) and of the HC (unburned hydrocarbons)
contained in the exhaust gases, changing them into
carbon dioxide and steam, respectively.
Due to the catalytic reaction, the high temperature
reached by the exhaust gases allows the burning of
the oil particles, thus keeping the silencer clean and
eliminating the exhaust fumes.
2
To have the catalytic converter function correctly and
for long and to reduce possible problems regarding
the soiling of the thermal unit and of the exhaust, it is
necessary to avoid covering long distances with the
engine running at constantly low rpm.
It is sufficient to alternate these periods with periods
in which the engine runs at relatively high rpm, even
if only for a few seconds, but rather frequently.
What has been stated above assumes particular im-
portance for the cold starting of the engine: in this
case, in order to reach a rpm regime sufficient to en-
able the "priming" of the catalytic reaction, just make
sure that the temperature of the thermal unit has
reached at least 50°C, which generally occurs a few
seconds after starting the engine.
b
Do not use leaded petrol, since it causes
the destruction of the catalytic converter.
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