KTM 250 SX-F 2005, Repair Manual

Page: 65 / 125

5-20
Repair manual KTM 250 SX-F
Art.-No. 3.206.027-E
Shift mechanism
– Check the shift forks
1
on the leaf
A
for wear. The forks have a
thickness of 4.8 to 4.9 mm when new, the wear limit is 4.6 mm.
– Check the shift grooves
B
on the shift drum
2
for wear.
– Check the fit of the shift drum in the grooved ball bearing
3
.
– Check the grooved ball bearing
3
for smooth operation.
– Check the shaft rollers
4
for pressure points and cracks.
– Check the shift rails
5
for runout on an even surface. Check the
shift rails for score marks and seizing marks. The shift forks must
operate smoothly on the shift rails.
– Check the shift rail
6
at the contact areas
C
for wear. Check the
return surface
D
on the shift rail for wear (replace in case of severe
indentation).
– Check the guide bolt
E
for a tight fit and wear.
– Pre-mount the shift shaft and check the clearance
F
between the
shift rail
6
and the shift quadrant. The clearance must lie between
0.40 - 0.80 mm.
F
7
bk
6
8
9
bl
Pre-mounting the shift shaft
– Clamp the short end of the shift shaft in a vise (use
protective jaws).
– Mount the shift rail
6
with the guide bolt facing
down and attach the guide bolt to the shift
quadrant.
– Mount the pressure spring
7
.
– Slide on the spring guide
8
, slide the return spring
9
over the spring guide with the angled end up
and lift the angled end over the dolly bolt
bk
(see
illustration).
– Mount the stop disk
bl
.