Yamaha XT660R(S) Automobile User Manual


 
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CHK
ADJ
CHECKING THE IGNITION TIMING/
MEASURING THE COMPRESSION PRESSURE
4. Detach:
timing light
5. Install:
timing mark accessing screw
EAS00067
MEASURING THE COMPRESSION
PRESSURE
NOTE:
_
Insufficient compression pressure will result in
a loss of performance.
1. Measure:
valve clearance
Out of specification Adjust.
Refer to ADJUSTING THE VALVE
CLEARANCE.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Disconnect:
spark plug cap
4. Remove:
spark plug
CAUTION:
_
Before removing the spark plug, blow away
any dirt accumulated in the spark plug well
with compressed air to prevent it from fall-
ing into the cylinder.
5. Install:
compression gauge 1
adaptor (compression gauge) 2
Compression gauge
90890-03081
Adaptor (compression gauge)
90890-04082
1
2