Yamaha YZ450F 2020 Owner's Service Manual page 209

Bolt (camshaft cap)
10 N·m (1.0 kgf·m, 7.4 lb·ft)
TIP
• Before installing the clips, cover the cylinder
head with a clean cloth to prevent the clips
from coming off into the cylinder head cavity.
• Apply the engine oil to the threads and contact
surfaces.
• Tighten the bolts to the specified torque in two
or three steps in the proper tightening se-
quence as shown.
ECA24630
NOTICE
The bolts (camshaft cap) must be tightened
evenly, or damage to the cylinder head, cam-
shaft caps, and camshaft will result.
7 7
4 4
E
2. Install:
• Timing chain tensioner
a. While pressing the tensioner rod lightly
with your fingers, use a thin screwdriver to
wind the tensioner rod up fully clockwise.
b. With the tensioner rod fully wound and the
chain tensioner "UP" mark "a" facing up-
ward, install the gasket "1", the timing
chain tensioner "2", and the gasket "3",
and tighten the bolts "4".
Bolt (timing chain tensioner)
10 N·m (1.0 kgf·m, 7.4 lb·ft)
2 2 3 3 5 5
1 1 6 6
1 1
c. Release the screwdriver, check that the
tensioner rod comes out smoothly, and
tighten the gasket "5" and the cap bolt "6".
Tensioner cap bolt
6 N·m (0.6 kgf·m, 4.4 lb·ft)
3. Turn:
• Crankshaft
Counterclockwise several turns.
4. Check:
• Top dead center (TDC) mark on the genera-
tor rotor
Align with the crankcase alignment mark.
• Camshaft match marks
Align with the cylinder head surface.
Out of alignment  Adjust.
5. Install:
• Timing chain guide (top side) "1"
• Cylinder head cover gasket "2"
• Gasket (spark plug hole) "3"
• Cylinder head cover "4"
• Bolt (cylinder head cover) "5"
Bolt (cylinder head cover)
10 N·m (1.0 kgf·m, 7.4 lb·ft)
TIP
Before installation, apply the sealant to the cylin-
der head cover gasket.
5-19
CAMSHAFT
3 3
a a
4 4
4 4
2 2 2
5 5
6 6
New
New