NOTE
Use the battery which is fully charged.
Special Tools - Compression Gauge, 20 kgf/cm²: 57001-221 Compression Gauge Adapter, M10 × 1.0: 57001-1601 L-Shape Hose [C]: 57001-1606

Cylinder Compression
Usable Range: 1 099
1 668 kPa (11.2
17.0 kgf/cm²,
159
242 psi) at 320 r/min (rpm)
The following table should be consulted if the obtainable compression reading is not within the usable range.
| Problem | Diagnosis | Remedy (Action) |
| Cylinder compression is higher than usable range | Carbon accumulation on piston and in combustion chamber possibly due to damaged valve stem oil seal and/or damaged piston oil rings (This may be indicated by white exhaust smoke). | Remove the carbon deposits and replace damaged parts if necessary. |
| Incorrect cylinder head gasket thickness | Replace the gasket with a standard part. | |
| Cylinder compression is lower than usable range | Gas leakage around cylinder head | Replace damaged gasket and check cylinder head warp |
| Bad condition of valve seating | Repair if necessary. | |
| Incorrect valve clearance | Adjust the valve clearance. | |
| Incorrect piston/cylinder clearance | Replace the piston and/or cylinder. | |
| Piston seizure | Inspect the cylinder and replace/repair the cylinder and/or piston as necessary. | |
| Bad condition of piston ring and/or piston ring grooves | Replace the piston and/or the piston rings. |
Cylinder Head
Cylinder Head RemovalExhaust Pipe Removal
Remove:
Radiator (see Radiator and Radiator Fan Removal in the
Cooling System chapter)
Exhaust Pipe Clamp Bolt [A] (Loosen)
Remove the exhaust pipe holder nuts [A], and pull out the
exhaust pipe [B] forward from the premuffler chamber.
...
Drive Chain Wear Inspection
Remove the chain cover (see Drive Chain Removal/Installation
in the Final Drive chapter).
Rotate the rear wheel to inspect the drive chain for damaged
rollers, and loose pins and links
If there is any irregularity, replace the drive chain.
Lubricate the drive chain if it appears dry.
...
Intake Air Pressure Sensor #1 Output Voltage Inspection
Measure the output voltage at the intake air pressure sensor
#1 in the same way as input voltage inspection, note
the following.
Disconnect the intake air pressure sensor #1 connector
and connect the measuring adapter [A] between these
connectors.
[B] Main Harness
[C] Intake Air Pressu ...