Yamaha RS90K, Service Manual

Page: 78 / 841

2-18
INSP
ADJ
COMPRESSION PRESSURE MEASUREMENT/
ENGINE OIL LEVEL INSPECTION
Measurement steps:
• Turn the main switch to “ON”.
• With the throttle wide open, crank the engine
until the reading on the compression gauge sta-
bilizes.
WARNING
To prevent sparking, ground all ignition coil
leads before cranking the engine.
NOTE:
The difference in compression pressure between
cylinders should not exceed 100 kPa (1 kg/cm
2
,
14.2 psi).
6. Install:
• Spark plug
Compression pressure (at sea level):
Standard:
1,450 kPa (14.5 kg/cm
2
, 206 psi)
at 400 r/min
Minimum:
1,260 kPa (12.6 kg/cm
2
, 179 psi)
at 400 r/min
Maximum:
1,620 kPa (16.2 kg/cm
2
, 230 psi)
at 400 r/min
T
R
.
.
Spark plug:
13 Nm (1.3 m · kg, 9.4 ft · lb)
ENGINE OIL LEVEL INSPECTION
1. Inspect:
• Engine oil level
CAUTION:
Do not run the engine with too much or not
enough oil in the oil tank. Oil could flow into the
air filter and the engine could be damaged.