Checking The Spark Advance - PIAGGIO Beverly 125 Service Station Manual

Beverly 125
Carburettor
- Disassemble the carburettor in its parts, wash all of them with solvent, dry all body grooves with
compressed air to ensure adequate cleaning.
- Check carefully that the parts are in good condition.
- The throttle valve should move freely in the chamber. Replace it in case of excessive clearance due
to wear.
- If there are wear marks in the chamber causing inadequate tightness or a free valve slide (even if it
is new), replace the carburettor.
- It is advisable to replace the gaskets at every refit
WARNING
PETROL IS HIGHLY EXPLOSIVE ALWAYS REPLACE THE GASKETS TO AVOID PETROL LEAKS

Checking the spark advance

- To check ignition advance, use the stroboscopic
light with induction pincers connected to the spark
plug power wire.
- Connect the induction pincers being careful to
respect the proper polarity (the arrow stamped on
the pincers must be pointing at the spark plug).
- Place the light selector in central position (1 spark
= 1 crankshaft turn as in 2-T engines).
- Start the engine and check that the light works
properly and the rpm indicator can read also the
high rpm (e.g. 8000 rpm).
- If flash unsteadiness or revolution reading error
is detected (e.g. half values), increase the resistive
load on the spark plug power line (10 ÷ 15 KΩ in
series to HV wire).
- Remove the plastic cover from the slot on the flywheel cover.
- Operating on the flash corrector displacement of the bulb, make the reference on the flywheel cover
coincide with level on the water pump drive. Read the advance degrees indicated by the stroboscopic
light.
Characteristic
Ignition advance
10° ± 1° at 2,000 rpm
- Make sure the advance degrees match the rotation rpm.
- If failures are found, check the Pick-Up and the control unit power supply (positive-negative), replace
the control unit if necessary.
Maintenance
MAIN - 39