KTM 50 SX JUNIOR - Manual (Page 27)

MAINTENANCE WORK ON CHASSIS AND ENGINE
»
ENGLISH
26
Tires, air pressure
Tire type, tire condition, and air pressure level affect the way your motorcycle
rides, and they must therefore be checked whenever you are getting ready to
go anywhere on your motorcycle.
– Tire size can be found in the technical specifications.
– Tire condition has to be checked every time you want to ride your motor-
cycle. Before leaving, check tires for punctures and nails or other sharp
objects that might have become embedded in them.
– Regularly check the "cold" tire pressure. Correct tire pressure (1.0 bar /
14 psi) guarantees optimum grip and maximum tire life.
– Damaged tires must be replaced immediately to protect your youngster.
– Worn tires can have a negative effect on how the motorcycle performs,
especially on wet surfaces
– Tire pressure below the normal level will lead to premature tire wear.
Checking spoke tension
The correct spoke tension is very important for the stability of the wheels and
thus for riding safety. A loose spoke causes the wheel to become
unbalanced and before long other spokes will have come loose. Check spoke
tension, especially on a new motorcycle, at regular intervals. If necessary, have
the spokes retightened and the wheel centered by a KTM dealer.
– Spokes can tear if you continue to ride with them loose. This may lead to
an unstable handling of your motorcycle.
– Excessively tensioned spokes may rupture due to local overloading. The
spokes must be tensioned to 2.5 - 3 Nm.
Cooling system
The water pump [1] in the engine keeps the cooling liquid in circulation.
The cooling liquid is cooled by the air stream. Therefore, the cooling effect
is reduced when the traveling speed is reduced. Dirty radiators additionally
reduce the cooling effect.
The cooling liquid can be drained by removing screw [2] on the water-pump
cover.
Do not remove any cooler hoses or the drain screw when the engine is hot.
A mixture of 50 % antifreeze and 50 % distilled water is used as the cooling
liquid. How-ever, the antifreeze protection must be at least -25° C (-13° F).
This mixture offers antifreeze protection but also good corrosion protection
and should therefore not be replaced by pure water.
For the cooling system, use only with high-grade antifreeze (Motorex Anti-Freeze).
Using lower-grade antifreeze agents can cause corrosion and coolant
foaming.
Pressure induced by heating of the coolant in the system is controlled by
a valve in the radiator cap [3]; a water temperature rising up to 120° C
(248° F) is admissible without fear of problems.
1
2
3