‘74 GT550 wiring help needed

[pgb123]

First question: if I disconnect the coils’ connector under the tank and then using a multimeter on continuity with one lead on the engine, when I touch the other lead to the orange/white wires in the connector, I get continuity, is that a problem?

Also, having disconnected the kill/starter connector in the headlight bowl, I get continuity between the head light ground and both the orange/white wire and the green/yellow wire.

Third, when testing resistance on my rectifier, I get small resistance in both directions. My manual says this shouldn’t happen

Finally, testing the green and orange wires on the regulator, when I push the armature to make contact, no ohm reading (or maybe it was infinite. Now I can’t recall). The manual says I should get 10 ohms.

I don’t really have any experience using a multimeter to track down wiring issues and would be grateful for any tips.

This all started after I ran the bike after sitting for some time. It started up, but ran poorly. Then I pulled the carbs to clean them, reinstalled and attempted to time the points. I’m trying to time the points, I found that my multimeter would continuously tone whether the points were open or closed.

[jabcb]

Dwell is about 180 degrees. (The points are closed for about 180 degrees of rotation.)
So one or two points are always closed.

With everything wired up when you are using the multimeter to set the points.
With good points closed, you get a reading of about zero ohms. (You get the internal resistance of the multimeter.)

With good points open, the circuit is closed via the coil + other coil + the other points that is closed. Or 8 or so ohms.
So your multimeter needs a much higher resistance to stop the tone.

To set the points turn the tone off & look at the reading.
Alternatively if you still have the coils disconnected you can use the tone because the points-coil-coil-points circuit is not there.

[pgb123]

Thanks so much for the reply. That is very helpful. So I’ve been chasing my tail here! I actually pulled the points plate, so now I see that the meter tones when each point is open and the toning stops when the points are open, except that the left point doesn’t tone when closed. I cleaned it with some 2,500 grit sandpaper, but no difference so I’ll replace that one, put it back on the bike and set and time with the coils disconnected.

Is the continuity between ground and the orange/white wire, ground and the green/yellow wire and ground an issue?

[jabcb]

No. It’s ok.

The wiring diagram is here: http://www.suzuki2strokes.com/forum/vie ... 3&start=15

For the voltage regulator:
black is ground
orange is power from the battery
green sends that power to the alternator rotor

The regulator uses a relay to control the voltage:
resistance orange to black: continuity - resistance of the relay coil
resistance orange to green: continuity - resistance varies depending on voltage with minimum of zero