Removing The Rocker Arms And Camshaft; Checking The Camshaft - Yamaha XG250 Service Manual

EAS23770
REMOVING THE ROCKER ARMS AND
CAMSHAFT
1. Loosen:
Locknuts "1"
●
Valve clearance adjusting screws "2"
●
Stopper plate "3"
●
3
2. Remove:
Camshaft "1"
●
Bearing; "2"
●
NOTE:
Screw 10 mm (0.396 in) bolt "3" into the thread-
ed end of the camshaft and then pull out the
camshaft.
1
3. Remove:
Intake rocker arm shaft
●
Exhaust rocker arm shaft
●
Intake rocker arm
●
Exhaust rocker arm
●
NOTE:
Remove the rocker arm shafts with the slide
hammer "1" and weight "2".
Slide hammer bolt
90890-01083
Slide hammer bolt 6 mm
YU-01083-1
Weight
90890-01084
YU-01083-3
2
1
EAS23840

CHECKING THE CAMSHAFT

1. Check:
●
2. Check:
●
3. Measure:
●
2
3
5-13
ROCKER ARM, CAMSHAFT
Bearing
Damage/wear → Replace.
Camshaft lobes
Blue discoloration/pitting/scratches → Re-
place the camshaft.
Camshaft lobe dimensions "a" and "b"
Out of specification → Replace the camshaft.
Camshaft lobe dimension limit
Intake A
36.520–36.620 mm (1.4378–1.4417
in)
Limit
36.460 mm (1.4354 in)
Intake B
30.201–30.301 mm (1.1890–1.1930
in)
Limit
30.151 mm (1.1870 in)
Exhaust A
36.564–36.664 mm (1.4395–1.4435
in)
Limit
36.514 mm (1.4376 in)
Exhaust B
30.216–30.316 mm (1.1896–1.1935
in)
Limit
30.166 mm (1.1876 in)
2
1