Measuring The Compression Pressure - Yamaha XC50V Service Manual

MEASURING THE COMPRESSION PRESSURE

1
EAS00067
MEASURING THE COMPRESSION PRES-
SURE
NOTE:
Insufficient compression pressure will result in
a loss of performance.
1. Measure:
8valve clearance
Out of specification
Refer to "ADJUSTING THE VALVE
CLEARANCE".
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Remove:
8battery cover
8battery holder
Refer to "COVER AND PANEL".
4. Disconnect:
8spark plug cap
5. Remove:
8spark plug
cC
Before removing the spark plug, use
compressed air to blow away any dirt
accumulated in the spark plug well to
prevent it from falling into the cylinder.
6. Install:
8compression gauge 1
Compression gauge
90890-03081
YU-33223
7. Measure:
8compression pressure
Out of specification
and (d).
3-21
CHK
ADJ
Adjust
Refer to steps (c)