PIAGGIO 500 cc Service Manual page 185

The spark advance value can be obtained at any time
by means of the diagnosis tester 020460Y.
Using stroboscopic lamp 020330Y it is possible to
check if the spark advance, determined by the fuel
injection system, corresponds to that truly activated on
the engine.
Proceed as follows:
- Remove the transmission box cover. See chapter 3 -
AUTOMATIC TRANSMISSION
- Remove the plug for inspection of the TDC reference
made between the flywheel and the cover crankcase.
See chapter 5- FLYWHEEL HOUSING.
- Using the driving pulley, rotate the engine until the
reference alignment to identify the TDC is found.
- Reproduce the reference between the driving pulley
and the engine crankcase See figure.
Fuel injection
9
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