without one your scooter won't run.
it times the spark and sends the trigger
spark to your coil.
on a stock CDI it will only allow the motor to make about 7,500rpm
after that it stops sending the trigger spark
oilyhans
i own a scooter shop with rentals ,sales& racing parts.
i also appraise scooters for KBB.
2003 Vino classic stage 0.75
de-reged stock variator w/8g sliding weights.
1.5k rpm springs
42mph
2005 veniceLX ~70cc~upjet~1.5k rpm springs & 7gr sliders
46mph
KeyWest de restricted~8gr slide