Removing The Cylinder Head; Checking The Cylinder Head - Yamaha XG250 Service Manual

EAS24130

REMOVING THE CYLINDER HEAD

1. Align:
"I" mark "a" on the Pickup coil rotor
●
(with the stationary pointer "b" on the crank-
case cover)
b
a
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the Pickup coil rotor counterclockwise.
b. When the piston is at TDC on the compres-
sion stroke, align the "I" mark "c" on the cam-
shaft sprocket with the mark "d" on the
cylinder head.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Loosen:
Camshaft sprocket bolt "1"
●
3. Remove:
Timing chain tensioner cap
●
Timing chain tensioner "1"
●
(along with the gasket)
Camshaft sprocket bolt
●
Breather plate 2
●
Camshaft sprocket
●
Timing chain
●
NOTE:
To prevent the timing chain from falling into the
crankcase, fasten it with a wire.
4. Remove:
Cylinder head "1"
●
d
c
EAS24160

CHECKING THE CYLINDER HEAD

1. Eliminate:
Combustion chamber carbon deposits
●
(with a rounded scraper)
NOTE:
Do not use a sharp instrument to avoid damag-
ing or scratching:
Spark plug bore threads
●
1
Valve seats
●
5-7
CYLINDER HEAD
1
1