Yamaha WR250F Manuel D'atelier page 316

CAMSHAFTS
5. Remove:
Exhaust camshaft 1
G
Intake camshaft 2
G
NOTE:
Attach a wire 3 to the timing chain to prevent
it from falling into the crankcase.
INSPECTION
Camshaft
1. Inspect:
Cam lobe
G
Pitting/scratches/blue discoloration →
Replace.
2. Measure:
Cam lobe length a and b
G
Out of specification → Replace.
Cam lobes length:
Intake:
a 30.296 ~ 30.346 mm
b 22.45 ~ 22.55 mm
Exhaust:
a 30.399 ~ 30.499 mm
b 22.45 ~ 22.55 mm
3. Measure:
Runout (camshaft)
G
Out of specification → Replace.
Runout (camshaft):
Less than 0.03 mm (0.0012 in)
4 - 24
ENG
(1.1923 ~ 1.1947 in)
<Limit>: 30.196 mm
(1.1888 in)
(0.8839 ~ 0.8878 in)
<Limit>: 22.35 mm
(0.8799 in)
(1.1968 ~ 1.2007 in)
<Limit>: 30.299 mm
(1.1929 in)
(0.8839 ~ 0.8878 in)
<Limit>: 22.35 mm
(0.8799 in)