Am I using a Voltometer correctly?

I wanted to test the output power of my Moped's magento. It's a 6 volt system therefore the Voltometer should read 6 volts. I hooked one wire up the the cable (the one thats hooked up to the sprakplug) and I grounded the other one up the the Engine Block. My brother pedeled on the bike and it maxed out no more than 0.5 volts. Am I measuring the voltage correctly? Because if you think about it, the wire keeps producing surges of electricity and Im wondering, because its a surge of electricity not a flow(Like a battery) maybe I'm niot testing it right.

Re: Am I using a Voltometer correctly?


I think your problem is that you're hooking your positive lead to the spark plug wire. The spark plug gets a high-voltage pulse. You need to hook one wire to ground (like you're doing) and the other to the positive terminal on your headlight or horn.

Re: Am I using a Voltometer correctly?

Batteries are DC. Magnetos produce AC (alternating current), and the amount of voltage varies with RPM.

If i hook a volt meter to my tail light and rev the engine, voltage will vary from about 8 to near 30 volts.

If there is a rectifier in the circuit, it will help chop and flatten the AC to something resembling DC.. but you won't ever see anything like the flat, steady current a battery delivers.

Re: Am I using a Voltometer correctly?

I had the same problem as Steve here, and had the voltage tested by a mechanic friend. Maybe he didn't know what he was doing in this case because I got results like Steve's. Can I still test voltage if my light bulbs are missing and I don't know if my horn works? The wires to these parts come right from the stator plate, I don't know if someone did a crappy rewiring job or what, so it seems like I would have the same problem as I did when measuring from the coil wire (pre coil).

Re: Am I using a Voltometer correctly?

Jonas Quimby /

And what's more, the spark plug coil takes the questionable AC power and ramps it up to a few thousand volts to the spark plug wire. But only for a fraction of a second every time the engine turns over.

That's why you cant measure a steady power output from your spark plug wire.

I'm surprised you didnt ruin your multimeter trying though.

Re: Am I using a Voltometer correctly?

Well guys? I need an answer here! Please?

Here's the deal: I had to replace my coil to even get a spark, and the replacement coil was not identical to my old one. I have spark now, but it is weak, and the fuel isn't lighting off. The "new" coil is an old Novi, so I'm not sure if it's a 12 or 6 volt coil. I need a 6 volt. If it's for a 12 volt, I imagine that the spark will be weak on a 6volt system. Am I right?

So if I assume that I have the right coil, and the voltage may not be able to be tested (see issues in my last post), how am I supposed to know if it's something in the stator plate?

How does one test a condensor to see whether it is good or not?

Finally, can the bike run if the lighthing/horn coil is bad?

Am I asking enough questions?

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