Measuring The Compression Pressure - Yamaha YFM45FAR Service Manual

CHECKING THE IGNITION TIMING/

MEASURING THE COMPRESSION PRESSURE

4.Detach:
Timing light
G
Inductive tachometer or engine tachometer
G
5.Install:
Seat
G
Fuel tank side panel (right)
G
Refer to "SEAT, CARRIERS, FENDERS
AND FUEL TANK".
MEASURING THE COMPRESSION
PRESSURE
NOTE:
Insufficient compression pressure will result in
a loss of performance.
1.Check:
Valve clearance
G
Out of specification → Adjust.
Refer to
CLEARANCE".
2.Start the engine and let it warm up for
several minutes.
3.Stop the engine.
4.Remove:
Seat
G
Fuel tank side panel (right)
G
Refer to "SEAT, CARRIERS, FENDERS
AND FUEL TANK".
5.Remove:
Spark plug
G
6.Attach:
Adapter
G
Compression gauge 1
G
Compression gauge:
P/N. YU-33223, 90890-03081
Adapter:
P/N. YU-33223-3, 90890-04082
3 - 21
CHK
ADJ
"ADJUSTING THE VALVE