1979 XS650 Chop won't start

It would be a good thing to test for quality of the spark. Use a spare spark plug and attach a short length of #12 house wire to the plug body using a hose clamp. Put an alligator clip on the end of the wire. Warm the engine up for a few minutes. Shut off the engine, and clip the alligator clip to an engine cooling fin. Remove one of the spark plug leads and attach it to your "test spark plug". Start up the engine running on just one cylinder, and in a dark garage, you'll be able to see how good your spark is.
Spark tester.JPG
 
It would be a good thing to test for quality of the spark. Use a spare spark plug and attach a short length of #12 house wire to the plug body using a hose clamp. Put an alligator clip on the end of the wire. Warm the engine up for a few minutes. Shut off the engine, and clip the alligator clip to an engine cooling fin. Remove one of the spark plug leads and attach it to your "test spark plug". Start up the engine running on just one cylinder, and in a dark garage, you'll be able to see how good your spark is.View attachment 96263
Is this ok to do with that aftermarket ignition? I don't want to fry anything.
 
Is this ok to do with that aftermarket ignition? I don't want to fry anything.
Yes, I have a Pamco ignition and that's how I test for quality of the spark. The important thing is to always have a path ( for both spark plugs) for the spark energy to go to ground. The tester plug is grounded via the wire and the alligator clip to the engine fin. The other plug is grounded in the normal way, screwed into the engine. Don't leave the power on to the ignition/Pamco/coil for any longer than needed i.e. only have power on when the engine is running.
 
My guess is the timing is just off. I have spark, getting fuel, it starts for a second and dies. Timing right? I've adjusted the PAMCO to every possible position and kicked this thing till my leg went numb. Im going to get on some research now to see if I can get some timing tips.
 
You have made a classic mistake that many lads make. You have changed too many systems on the bike at one time. You changed the alternator charging system, the ignition and the carbs all at once. That makes it difficult to trouble shoot.
Here's my suggestion. Remove the PMA and its rec/reg unit. Remove the Pamco ignition. Re-install the stock alternator with its stock rectifier and regulator and re-install the stock points ignition. Re-install a battery. Now the only new system is the carbs, so you can focus on getting the engine started and running with the new carbs, as the only questionable problem area..

Once the engine starts and runs normally, remove the points ignition and install the Pamco ignition. OK so once again, you have added only one new additional system. Focus on starting up and running with the Pamco.

Only after the engine starts and runs reliably with the new carbs and Pamco ignition, do you remove the stock alternator charging system, and re-install the PMA and its rec/reg.

Actually, I would just keep the stock alternator charging system/battery and forget about the PMA/capacitior crap. That PMA stuff has caused many problems over the years, and is an inferior system compared to the stock system. The PMA systems can also burn out the Pamco system (when the volts go crazy), while a stock alternator system with a battery, will not do that.

I also noticed your ATU fly-weights have a lot of wear on them, which means the advance curve will be expanded, and if you set the timing at the F mark, you will be past the fully advance mark. Running past the full advance mark could destroy your engine, when a hole is burned into the top of a piston(s). If you plan to stay with the Pamco, which is a good idea, it would be wise to buy the Pamco
E-advancer option.
 
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