Checking The Valves And Valve Guides - Yamaha YZF-R1 1998 Service Manual

VALVES AND VALVE SPRINGS
3. Remove:
4. Remove:
EB403400
CHECKING THE VALVES AND VALVE
GUIDES
The following procedure applies to all of
the valves and valve guides.
1. Measure:
4 - 24
• valve cotters 1
NOTE:
Remove the valve cotters by compress-
ing the valve spring with the valve spring
compressor 2 and attachment 3.
Valve spring compressor
90890-04019
Attachment
(for the intake valve)
90890-04114
(for the exhaust valve)
90890-04108
• upper spring seat 1
• valve spring 2
• valve 3
• oil seal 4
• lower spring seat 5
NOTE:
Identify the position of each part very
carefully so that it can be reinstalled in
its original place.
• valve-stem-to-valve-guide clearance
Valve-stem-to-valve-guide clearance =
Valve guide inside diameter a –
Valve stem diameter b
Out of specification → Replace the
valve guide.
Valve-stem-to-valve-guide
clearance
Intake
0.010 ~ 0.037 mm
<Limit>: 0.08 mm
Exhaust
0.025 ~ 0.052 mm
<Limit>: 0.1 mm
ENG