PIAGGIO 500 cc Service Manual page 208

Fuel injection
Start the engine and allow it to warm up until the following conditions are reached:
Regulation is correct.
On revealing non-conformant CO values adjust fuel injection timing to minimum.
Select the "CO PRECALIBRATION" function from the diagnosis tester menu
The display shows the words "TRIMMER VALUE".
The numeric indication may be positive or negative.
9 - 96
- coolant temperature = more than 70°C
- air intake temperature = 25 - 30°C
Activate the exhaust gas analyser and check
the following conditions:
- CO = 1.25±0.25%
- CO2 = 14.50±1%
YES
Activate the adjusting function.
NO