KTM 250 SX-F 2005, Repair Manual

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5-21
General information on servicing the transmission
Clamp the main shaft or countershaft in a vise (use protective jaws). Remove the gear wheels and check the following parts for
wear and seizing marks:
– Bearings
– Pivot points on the main shaft and countershaft and pivot points on the idler gears
– Shift dogs
– Tooth faces on all gear wheels
– Tooth profiles on the main shaft and countershaft as well as the corresponding gear
wheels
– Profiles of all sliding gears for smooth operation
Carefully clean all parts and replace any damaged parts.
Mount new circlips whenever you repair the transmission.
Assembling the main shaft
– Clamp the main shaft in the vise with the toothed end facing down (use protective jaws).
– Carefully oil all parts before mounting.
– Mount the split needle bearing
1
, mount the 5-speed idler gear
2
with the shift dogs
facing up.
– Mount the stop disk
3
(22x28,5x1mm) and circlip
4
with the sharp edge facing up.
– Slip on the 3rd/4th gear sliding gear
5
with the small gear wheel on the bottom and
mount the circlip
6
.
– Slip on the stop disk
7
and the split needle bearing
8
.
– Slip on the 6th gear sliding gear
9
with the recess facing up.
– Slip on the 2nd gear fixed gear
bk
with the collar facing down and mount the stop disk
bl
(17.2x24x1mm).
– Finally, check all of the gear wheels for smooth operation.
1
2
3
4
5
6
7
9
8
bk
bl