Suzuki VL800 Service Manual page 557

COMPRESSION PRESSURE CHECK
The compression of a cylinder is a good indicator of its internal condition.
The decision to overhaul the cylinder is often based on the results of a compression test. Periodic mainte-
nance records kept at your dealership should include compression readings for each maintenance service.
COMPRESSION PRESSURE SPECIFICATION (Automatic de-comp. actuated)
Standard
1 300 – 1 700 kPa
(13 – 17 kgf/cm², 185 – 242 psi)
Low compression pressure can indicate any of the following conditions:
* Worn-down piston or piston rings
* Piston rings stuck in grooves
* Poor seating of valves
* Ruptured or otherwise defective cylinder head gasket
Overhaul the engine in the following cases:
* Compression pressure in one of the cylinders is less than 1 100 kPa (11 kgf/cm², 156 psi).
* Difference in compression pressure between two cylinders is more than 200 kPa (2 kgf/cm², 28 psi).
* All compression pressure are below 1 300 kPa (13 kgf/cm² 185 psi) even when they measure more than
1 100 kPa (11 kgf/cm², 156 psi).
COMPRESSION TEST PROCEDURE
NOTE:
* Before testing the engine for compression pressure, make
sure that the cylinder head nuts are tightened to the specified
torque values and the valves are properly adjusted.
* Have the engine warmed up before testing.
* Make sure that the battery is fully-charged.
Remove the related parts and test the compression pressure in
the following manner:
• Lift and support the fuel tank. ( Page 14-93)
• Remove the all spark plug caps and outside spark plugs (#1 &
#2) [For E-02, 19 24, 33]. (Page 18-8)
• Install the compression gauge and adaptor in the spark plug
hole. Make sure that the connection is tight.
• Keep the throttle grip in the fully opened position.
• Press the starter button and crank the engine for a few sec-
onds. Record the maximum gauge reading as the cylinder
compression.
• Repeat this procedure with the other cylinder.
 09915-64512: Compression gauge set
09915-63210: Adaptor
Limit
1 100 kPa
(11 kgf/cm², 156 psi)
VL800/C/TK9 ('09-MODEL) 18-17
Difference
200 kPa
(2 kgf/cm², 28 psi)