Vespa Ciao, grounding headlight cuts engine

[wethepedalTopic starterBerichten: 2]

I finally finished putting together this ’72 Ciao. I am really happy with everything performance wise. Pulls really hard and tops maybe mid-high 30’s. I have a working tail light w/ brake light wired. The tail light is led. The headlight is a sealed 6V and works.

When I ground the headlight, it cuts the motor. I have grounded it in several spots (including the headlight bucket, engine mount bolt, cross bar, and the forks) and it will still cut the motor. I have hooked up just the tail light and it works without cutting the motor. I am stumped. I hope someone will be able to help me out with this one. Thank you.

Specs if interested:
-stock crank
-64 Malossi, Malossi head
-Case matched and intake opened
-13.13 w/ 66 jet, Malossi high-flow filter
-Techno Stinger pipe
-Malossi variator, I think ~48gr
-Malossi contra spring (yellow), not sure on gearing

[hansiebModeratorBerichten: 10922]

Eletronic or contact points ignition ?

This scheme is for electronic ignition

[wethepedalTopic starterBerichten: 2]

I have stock points setup. Everything is hard-wired. Here’s the way it’s wired. Thanks in advance.

Chris.

[Gebruiker]

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