KTM 50 SX - Manual (Page 28)

MAINTENANCE WORK ON CHASSIS AND ENGINE
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ENGLISH
27
Checking coolant level
The coolant should be 10 mm (0.4 in) above the radiator fins when the engine
is cold (see illustr.). In the event of the coolant being drained, always fill and
bleed the system.
If possible, always check level of cooling liquid when engine is cold. If you
have to open the radiator cap when the engine is hot, use a rag to cover the
cap and open slowly to release pressure.
Cleaning the air filter *
The air filter must be cleaned at intervals depending on the amount of dust
accumulated. To clean the air filter, first remove the seat. Then press both
retaining clips [1], remove the filter holder and the air filter [2]. The air
filter consists of a foam rubber insert soaked with filter oil.
– Do not clean the foam filter with fuel or petroleum since these will dam-
age the foam. KTM recommends the products (Motorex Liquid Bio Power)
for air filter maintenance.
– Never operate your motorcycle without an air filter. Otherwise, dust and
dirt may get into the engine and lead to increased wear.
– The holder must retain the air filter throughout its entire circumference.
If the filter has been mounted incorrectly, the engine will take in unfil-
tered air, thereby causing increased engine wear.
Thoroughly wash the foam filter in special cleaning fluid (Motorex Bio Dirt
Remover) and allow it to dry well. Only press out the filter, do not wring it out
under any circumstances. Oil the dry foam filter with a high-grade filter
oil ( Motorex Liquid Bio Power). Also clean the air filter box. Check carbure-
tor collar for damage and that it is filled correctly.
Insert the air filter in the opening and fasten it with the filter holder. Then
mount the seat.
Exhaust system *
The silencer is filled with glass-fiber yarn for damping. When in use, the glass-
fiber yarn becomes loose or coked with oil carbon. This can lead to a power
loss and a reduction of the silencer damping. The glass-fiber yarn packing
can be replaced in a few easy steps.
To replace, remove the silencer from the vehicle and mark the position of the
outer tube [3] to the inner tube [4]. Remove screws [5] and the end cap [6].
Pull of the outer tube and remove the old glass-fiber yarn packing [7] from
the inner tube. Thoroughly clean all parts.
To assemble, mount a new glass-fiber yarn packing onto the inner tube (see
illustration) and slide into the outer tube. Mount end cap and fix with
screws [5]. Before tightening the screws, turn the outer tube until they match
the positions you marked. Mount the silencer and check the exhaust system
for tightness.
Note: Glass fiber yarn packages are offered by your licensed KTM dealer.
The exhaust system becomes very hot while the motorcycle is running. to avoid
burns do not start work on the exhaust system until it has properly cooled
down.
2
7
5
6
3
4
when engine is cold
10 mm
1
1