72 Vespa Rally 180cc Electrical Problems HELP!

I've got a 1972 Vespa Rally 180cc (no battery) that keeps blowing all lights - it literally burns through the contact points. I've used a voltage measurer and it puts out between 6 and 30 volts (when you rev the motor) and blows all lights. I've replaced all the coils, checked the electrical wiring and replaced the switches on the handlebars- and still no luck. BTW- when I hit the back brake pedal (when they're working) all lights go out when pressed down and then on again when let off. All my friends who are scooter freaks cannot be bothered-they say the electrics on old models are always a pain. The only thing I can think of is that I should put in a voltage regulator and hope that works. Sorry, I'm kinda daft when it comes to fixing my scoot so any help would be greatly appreciated. I could really use some help here.. This has been a problem for 5 years now and I have only had headlight, and now even it's gone. Cannot drive at night-don't want to get busted or kill myself. [:)] Please, please please!!! HELP!!!!

6v system - no battery. I will check the coils. I've fitted all correct bulbs. Any other info you need i'd be happy to provide. :) btw - it's blown lights since I had the original coil also - I have an aftermarket one now though and think that it's not the problem. can post pics if needed. thanks again for your help. 


Hi i am no expert in 1972 vespa rally 180 but have lots of electrical experience and with out a doubt you have a voltage reg problem if it was coils it would be charge or no charge but not climbing with engine rpm  the brake light is separate problem it is a ground earth problem witch means when you press the pedal the switch is going to earth and blacking out the system that will take some close inspection to find but no problem if you have a multi meter

if you need any help i am glade to point you in the right area

Regards Clayton



Not sure if there is more background detail here but here are my thoughts. If you have a 6V system with no battery then you could have a coil issue. It could be the wrong coils or a faulty one. If you have a battery which some early rally's did then you may already have a regulator. Blown bulbs can also be because you do not have all bulbs fitted or a wrong bulb. The old systems relied on having the correct wattage bulbs else they would start blowing.

If you have a 12 v system (probably aftermarket) then you should have a regulator. I fitted a 12v system to a early 70's super and mounted the regulator in the left hand cowl. The regulator is only used for lights and horn. Most 12v conversions also change the electrics from usually shorted switched to more conventional usually open switches. This can catch some people out with the brake switch.

I can offer more advice but need to know the specific setup

Thanks! What would you suggest in terms of voltage regulation - and if I got one where to attach (and hide) it? 


Hi (again) guys,

I fixed the brake switch, got all the proper bulbs and have a new headlight replacement.. the sockets for the headlight and pilot light were crap... the only problem now being there is no fitting in the new bulb socket for the pilot light ground wire! It's an aftermarket part: http://www.sip-scootershop.com/en/main/base/Details.aspx?ProductNumber=57268800 and should be made as close to the original as possible. Any help? :) thanks in advance!