Yamaha 2011 WR250FA Owner's Service Manual page 153

REMOVING THE CAMSHAFT
1. Remove:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw "2"
2. Align:
• T.D.C. mark
With align mark.
Checking steps:
a. Turn the crankshaft counterclockwise with a
wrench.
b. Align the T.D.C. mark "a" on the rotor with
the align mark "b" on the crankcase cover
when piston is at T.D.C. on compression
stroke.
In order to be sure that the piston is at Top
Dead Center, the punch mark "c" on the ex-
haust camshaft and the punch mark "d" on the
intake camshaft must align with the cylinder
head surface, as shown in the illustration.
3. Remove:
• Timing chain tensioner cap bolt "1"
• Timing chain tensioner "2"
• Gasket
4. Remove:
• Bolt (camshaft cap) "1"
• Camshaft cap "2"
• Clip
Remove the bolts (camshaft cap) in a criss-
cross pattern, working from the outside in.
The bolts (camshaft cap) must be removed
evenly to prevent damage to the cylinder
head, camshafts or camshaft caps.
5. Remove:
• Exhaust camshaft "1"
• Intake camshaft "2"
Attach a wire "3" to the timing chain to prevent
it from falling into the crankcase.
5-20
CAMSHAFTS