Raider 50, Service Manual

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Maintenance
5. Install compression gauge 2 to plug hole.
2
Compression Gauge:
P/N. 3AC-99030-0
6. Set throttle grip to full open position, crank engine until
compression gauge indication stabilizes, and then
measure compression pressure.
Compression Pressure (Reference):
0.80 MPa (117 psi) [8.2 kgf/cm
2
]
Different between compression pressure of each
cylinders:
within 0.105 MPa (15 psi) [1.05 kgf/cm
2
]
Compression pressure is affected much by
cranking speed, and normally changes in the
range from 10% to 20%.
7. If compression pressure is below specified value or varies
much among cylinders, put small amount of engine oil into
cylinders, and perform the test again.
· If compression pressure increases after the
above measure, check pistons and piston rings for
wear. Replace if necessary.
· Check cylinder head gasket if the compression
pressure does not rise. Adjust or replace if
necessary.
If any of the following results is obtained by the
measurement, it is necessary to repair or replace relevant
part(s).
· The measurement is lower than specified value,
· Different between compression pressure of the cylinders
exceeds ; 0.105 MPa (15 psi) [1.05 kgf/cm
2
], or
· The measurement is abnormally higher than specified
value.
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