A clarification in order here....

The 2 voltage regulator terminals are marked 'Batt' and 'Gen' if it is a Delco-Remy brand. These are the two terminals you momentarily flash.

The terminals are called 'B+' and 'D+' if it is a Bosch. Likewise, these are the 2 terminals you momentarily flash.

Or, another way to do it is flash the 'A' terminal on the generator with the positive battery post, but I am trying to make it simple and the voltage regulator is the 'go to' location to flash the fields because it is easy to get to these terminals.

Never ground the 'generator F' connection while the engine is running or the switch turned on. That will fry the regulator points........ pg

 

This might be my first bike but I have worked on cars before. Anyways, I do have a multimeter that reads dc and ac current. Yes, it's a good one. It was passed down from my father.

 

Pardon me, but you are the first person I have run into who has a DC ammeter. Congrats, and yes that will work fine.
You want to be reading in the area of 0 to 15 amps so set it however you set it to read that range.
I'd say you are now cleared for take off. Let us know if the generator is good (puts out 10 amps or more) and then we can go from there...... pg

 

Ok. Just ran the test. Did as said and with the choke/enricher wide open (she was cold, and I'm guessing revving above 2000rpm) I was reading over 20 amps from the generator. So I don't know what to think about that. Anyways, just running off the FULL battery and testing the generator she yet again died. This was about maybe a minute or two into the test. And then trying to start her again she putted up a few times but nothing sustainable.

WHAT is going on!? With that amperage I guess it doesn't look like the generator is the problem. And with a FULL battery just charged last night I would have thought that the engine would run off the battery for more than it did.

And to top it off I knocked off the ground cable's "eye" connect to the battery. It was old and I guess didn't hold on when I was trying to kick start her. So it broke off. Got to get that fixed. Any ideas there?

Please help. This is frustrating. What do you think this could be???

 

You are making progress. Don't get frustrated.
From the results of the test, the generator is good. Be very happy about that.

Now, just because the engine died and did not want to start easily again, do not think it has anything to do with the battery being low.
You said yourself that the bike was not warmed up good. Sportster does not run well until it is at operating temperature.
I believe you will find the problems of running in either the ignition or the carb.... or both. You have to just take it one step at a time.

Turn on your headlights. Do they light up? If they do there is plenty of battery juice to start and run the bike.
The starter needs a strong battery but the ignition needs very little.

If I understood you correctly you broke a post off of the battery? If so, just go buy a new battery. Don't monkey around with trying to use the old one as it is done for........ pg

 

I'm sorry, I didn't explain my "break" mishap. I broke off the eyelit on the cable that connects the "-" terminal on the battery to the Harley's frame.

So, thinking about this problem a little more. The battery is good, the generator is good. When I get her started up again I'm going to check the voltage across the battery when she is revved. I think if the voltage spikes with the rpm then the voltage regulator is fine. If not, maybe that's the problem.

So, looking back in the history of this problem she starts...then dies. Then I can't seem to start her up again. Heat may be a factor. If she is getting warm, and then dies, then maybe heat is being a factor. Am I correct to say that the ignition is breaker-less? The points don't connect, right? Maybe if they're worn down, they expand with the heat causing too much of a gap for ignition? Just a thought.

Or...maybe something is stuck in the fuel system. If there is plenty of juice to run the ignition from the battery, then it must be heat or fuel (or the lack thereof) causing the dying.

Ideas/suggestions/advice?

Thanks for this help. Much appreciated. I need to get her back on the road.

Oh, and yes, the headlight is just fine. Bright as the sun.

 

OK, I misunderstood. The cable just needs a new ferrule installed on the cable. Or since it is the ground you can just bolt it down to the frame with a bolt and flat washer over the cable. A ferrule is the better fix though.

I would say your generator is working, the battery is good, as it burns the lights.

There are 2 ways to test the voltage regulator.
Method 1 is to use a separate multimeter, ammeter,fixed resistances of ¼ ohm and 1½ ohm, and 25 watt variable field resistor.

Method 2 uses the same items in a single unit (made by Sun Equipment Corp) called a Vat 26 volt-ampere tester with a variable load resistance.

Myself, I do not own any of this stuff.
Let me know if you do, and I can give you the instructions on how to do the test.

Your 1978 came with ignition points. Someone may have installed an electronic ignition on it to replace the points.
The way to tell is remove the round plate on the timing cover and look inside. You should see points and a condenser.

Assuming you have the points set up, the point gap should be set at .018.
Note, there is an ignition cam on which the foot of the points rides on.
The tall narrow lobe is for the front cylinder.
The wider, fatter lobe is for the rear cylinder. Check the gap for the front cylinder and for the rear cylinder. Each should be .018 in a perfect world. The difference between the 2 gaps should be .004 or less. If it is greater than .004, buy a new ignition cam because the one you have is worn.

This is a good place to start. I will not get into more detail yet. Check the points gap(s) and let's see what you find......... pg

 

Quick question: Just glancing real quick at the distributor, it seems real tucked away under the front part of the gas tank. I'm guessing for easy of viewing I'll have to take my gas tank off to get at it?

 

OK, a Sportster does not have a distributor. When you say up under the tank, you must be looking at the ignition coil. This is a black lump with the spark plug wires coming out of it. See the pic of a coil....



The points will be behind the round cover on the timing cover. Remove the 2 screws, the round plate and the solid gasket behind the plate. Now you are looking at the points and condenser. See pic.......



The points cover is the round one just above the shift lever (right hand side) in this pic of my bike.
Your shift lever is on the left side because yours is a later model, but your points will be on the right side behind this cover......... pg

 

gee you broke off connection for ground i think thats your prob. bad ground go to auto parts store take old with you so you get correct length.it could have been bad all along