PIAGGIO 500 cc Service Manual page 239

Starting
Activate engine ignition (with vehicle movement blocked) for sufficient time to note the revolutions and
absorption of the starting motor.
Absorption in running speed: from 80 to 120A
Running speed: from 300 to 400 rpm
N.B.: The stated revolutions value is that indicated by the diagnosis tester. The revolutions reading does not
correspond to the actual revolutions, however it is valid for the diagnosis.
YES
The values are correct
For final confirmation, carry out a blank
absorption control.
Remove the starting motor (see Chapter 6-
FLYWHEEL AND STARTING SYSTEM).
Reconnect the earth and positive and
carry out the control.
Blank absorption of current: < 40A
YES NO
The motor is efficient Check rotor rotation
NO
Low running speed
High electrical absorption
Check the engine revolution
(e.g.: possible fusion of the brasses)
and if no anomalies are revealed, replace the starting motor.
NO
Low running speed
Low electrical absorption
Repeat the test connecting the solenoid starter power terminals or
proceed with replacement.
Check the new values.
YES NO
Replace definitively the solenoid starter Repeat the battery controls
and if necessary replace
the starting motor.
NO
High running speed
Low electrical absorption
The engine turns too easily; check the compression end pressure
(see Chapter 1-GENERAL INFORMATION AND MAINTENANCE).
On revealing incorrect values, proceed as indicated.
N.B.: If the running speed of the driving shaft proves to be low and is coupled with anomalous noise, proceed with
checks of the free wheel and the torque limiter (see Chapter 6- MAGNETO FLYWHEEL AND STARTING SYSTEM.
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