KTM 450 SX Motorcycle User Manual


 
ENGLISH
30
MAINTENANCE WORK ON CHASSIS AND ENGINE »
Breather plug front fork
After every 5 hours of use for competitive racing, slacken the breather
plugs [1] a few turns in order to relieve excess pressure from the inside of the
fork. To do this, place the motorcycle on a stand with the front wheel lifted
off the ground. When riding the motorcycle mainly on the road, it will suffice
to have this job performed in the course of the periodical maintenance
service.
EXCESSIVE PRESSURE IN THE INTERIOR OF THE FORK CAN CAUSE LEAKS IN THE
FORK. IF YOUR FORK IS LEAKING, IT IS RECOMMENDED TO OPEN THE BREATHER
PLUGS BEFORE HAVING THE SEALS REPLACED.
Clean the dust-protection bellows, outer tubes, and fork tubes thoroughly, and
oil them thoroughly with Universal oil spray (Motorex Joker 440) or engine
oil. Then, push the dust-protection bellows into the outer tubes by hand.
NO OIL MAY REACH THE FRONT TIRE OR THE BRAKE DISKS SINCE THIS WOULD
CONSIDERABLY REDUCE THE TIRE'S ROAD GRIP AND THE BRAKING EFFECT OF
THE FRONT BRAKE.
Checking and adjusting the steering head bearing *
Check steering head bearing for play periodically. To check, put the motorcy-
cle on a stand so that the front wheel is off the ground. Now try to move the
fork forward and backward. For readjusting, loosen the five pinch bolts [3]
and [5] of the top triple clamp and turn steering stem bolt clockwise [4] until
there is no more play. Don’t tighten the steering stem bolt all the way, other-
wise the bearings will be damaged. With a plastic hammer, lightly tap on the
triple clamp to release tension. Retighten the five pinch bolts to 20 Nm (EXC)
and 17 Nm (SX).
IF THE STEERING HEAD BEARING IS NOT ADJUSTED TO BE FREE OF PLAY,
THE MOTORCYCLE WILL EXHIBIT UNSTEADY DRIVING CHARACTERISTICS AND
CAN GET OUT OF CONTROL.
A PLASTIC INSERT IN THE THREAD OF THE CLAMPING SCREW [5] MAKES IT
SELF-LOCKING. THE CLAMPING SCREW MUST BE REPLACED IF IT CAN BE
TURNED IN BY HAND.
IF YOU DRIVE WITH PLAY IN THE STEERING HEAD BEARING FOR LONGER PERI-
ODS, THE BEARINGS AND SUBSEQUENTLY THE BEARING SEATS IN THE FRAME
WILL BE DESTROYED.
The steering head bearings should be regreased at least once a year
(e.g. Motorex Long Term 2000).
1
2
Cleaning the dust sleeves of the telescopic fork
The dust-protection bellows [2] are to remove dust and coarse dirt particles
from the fork tube. However, after some time, dirt may also get in behind the
dust-protection bellows. If this dirt is not removed, the oil sealing rings located
behind it may start to leak.
Use a screwdriver to lift the dust-protection bellows out of the outer tubes
and slide them downward.
5
4
3
3