Need ideas on tachometer using ignition

Other Hardware Sensors
21

guys tell me if I can use this module to capture light signals

Photosensitive Sensor Module Light Detection Module for Arduino

and this neon bulb
Clear Neon Indicator Lamp

To connect to a spark plug ...
connect directly NEON wire to the ignition wire??
or neon wire wrapped several times around the ignition wire??

22

If your scooter has a battery, it probably has an alternator for charging. Use one phase of the alternator output as a tachometer input. I put one on my 1984 Chevy diesel pickup and it worked fine. Should work on your scooter, with a little fussing around with calibration.

Paul