Yamaha YZF-R1S Service Manual - Eng
5-23
CYLINDER HEAD
ENG
NOTE:
NOTE:
NOTE:
EAS00222
REMOVING THE CYLINDER HEAD
1. Remove:
Sintake camshaft
Sexhaust camshaft
Refer to “REMOVING THE CAMSHAFTS”.
2. Remove:
Scylinder head nuts
Scylinder head bolts
SLoosen the nuts in the proper sequence as
shown.
SLoosen each nut 1/2 of a turn at a time. After all
of the nuts are fully loosened, remove them.
EAS00227
CHECKING THE CYLINDER HEAD
1. Eliminate:
Scombustion chamber carbon deposits
(with a rounded scraper)
Do not use a sharp instrument to avoid damag-
ing or scratching:
Sspark plug bore threads
Svalve seats
2. Check:
Scylinder head
Damage / scratches
! Replace.
3. Measure:
Scylinder head warpage
Out of specification
! Resurface the cylin-
der head.
Maximum cylinder head warpage
0.10 mm (0.0039 in)
a. Place a straightedge
1
and a thickness
gauge
2
across the cylinder head.
b. Measure the warpage.
c. If the limit is exceeded, resurface the cylinder
head as follows.
d. Place a 400
X 600 grit wet sandpaper on the
surface plate and resurface the cylinder
head using a figure-eight sanding pattern.
To ensure an even surface, rotate the cylinder
head several times.