ENGLISH
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MAINTENANCE WORK ON CHASSIS AND ENGINE »
Replacing the glassfiber yarn packing of the silencer *
Aluminum silencers are filled with glassfiber yarn to muffle noise. Have the
filling checked regularly by an authorized KTM workshop (see Lubrication and
Service Chart). The insulating material fibers escape through the holes in the
perforated pipe with time, causing the silencer to „burn out“. In addition to
causing a higher noise-level, it will also affect the power characteristic. The
insulating material suitable for your exhaust is available from your authorized
KTM workshop.
By experience, the front glassfiber yarn packing [3] needs to be replaced more
often than the rear silencing mat [4].
For this purpose, remove the silencer from the vehicle and dismount the front
cap [5]. Pull the front glassfiber yarn packing together with the inner exhaust
pipe [6] out of the silencer. Clean the front inner exhaust pipe.
To facilitate the mounting procedure, you can make a mounting tool [7] out
of wood, plastic, or metal. Insert the mounting tool into the inner pipe and
mount the glassfiber packing. Push the inner pipe containing the packing into
the silencer such that the slot engages the web [A]. Use a blunt ended object
to stuff the glassfiber yarn packing all the way into the silencer, and mount
the front cap.
To change the rear silencing mat, start by removing the front packing and the
inner exhaust pipe. Then, drill open the rivets and remove the end cap [C].
NOTE:
In every exhaust repair procedure, the O-rings must be replaced by new ones.
Glass fiber yarn packings are available from your licensed KTM
mechanic.
Make sure the caps are screwed on tightly. Mount the muffler stress-free before
tightening the fixing screws.
THE EXHAUST SYSTEM BECOMES VERY HOT WHILE THE MOTORCYCLE IS RUN-
NING. TO AVOID BURNS DO NOT START WORK ON THE EXHAUST SYSTEM UNTIL
IT HAS PROPERLY COOLED DOWN.
Cleaning the spark arrester (XC/EXC USA) *
The spark arrester should be cleaned every time the glassfiber yarn filling is
changed or at least once annually.
For this purpose, dismount the silencer cap and remove any deposits that might
exist in region [B]. Renew the O-ring and mount the silencer cap.
2
1
Bleeding the cooling system (250 SX-F)
By removing the screw [1] at the water pump cover you can drain the coolant.
To bleed the cooling system, fill in approx. 1.0 liter (0.25 US gallons) of coolant
and remove the bleeder screw [2]. Do not reinstall the bleeder screw until
coolant escapes at the bore without any bubbles.
Then, fill in the coolant until it reaches a level about 10 mm above the
radiator fins.
After a short ride, check the coolant level once more.
B
SX
EXC
C
6
5
3
7
3
7
5
C
4
6
A
