Checking The Rocker Arms And Rocker Arm Shafts; Checking The Timing Chain And Camshaft Sprocket - Yamaha R1 Series 2015 Service Manual

Camshaft journal diameter
25.459–25.472 mm (1.0023–
1.0028 in)
EAS30259
CHECKING THE ROCKER ARMS AND
ROCKER ARM SHAFTS
The following procedure applies to all of the
rocker arms and rocker arm shafts.
1. Check:
• Rocker arm
Damage/wear Replace.
2. Check:
• Rocker arm shaft
Blue discoloration/excessive
ting/scratches Replace or check the lubri-
cation system.
3. Measure:
• Rocker arm inside diameter "a"
Out of specification
Rocker arm inside diameter
7.987–8.002 mm (0.3144–0.3150
in)
Limit
8.017 mm (0.3156 in)
wear/pit-
Replace.
4. Measure:
• Rocker arm shaft outside diameter "a"
Out of specification
Rocker arm shaft outside diame-
ter
7.967–7.979 mm (0.3137–0.3141
in)
Limit
7.936 mm (0.3124 in)
5. Calculate:
• Rocker-arm-to-rocker-arm-shaft clearance
TIP
Calculate the clearance by subtracting the rock-
er arm shaft outside diameter from the rocker
arm inside diameter.
Out of specification
Rocker-arm-to-rocker-arm-shaft
clearance
0.008–0.035 mm (0.0003–0.0014
in)
Limit
0.080 mm (0.0032 in)
EAS30258
CHECKING THE TIMING CHAIN AND
CAMSHAFT SPROCKET
1. Check:
• Timing chain
Damage/stiffness
chain and camshaft and camshaft sprocket
as a set.
5-16
CAMSHAFTS
a
Replace.
Replace.
Replace the timing
a