Engine Not firing, suspected carb issue

emptypond wrote: I have suppressed wires (Dyna), with the caps on the spark plugs and the 3ohm green dyna coils, with the dyna s ignition. My voltmeter is broken and I haven't picked another one up yet.

Multimeters are cheap; you can get a good one for around $20 and they are essential for troubleshooting these bikes.

Motor Head wrote: Spark Plug #?

#2 is lighting the lamp, the other 3 are not.
Those Dyna wires are suppression wires with plain caps built in. As long as he is using the standard NGK B8-ES plugs he is electrically correct.
With no multimeter, checking the color of the spark is a quick check. It should be blue or white. Red or yellow is a bad thing.

No double posting., Thanks for helping me. I've got white spark, not yellow. with brand new NGK B8 ES plugs. I'll pick up a multimeter tomorrow. I've needed one for a while but didn't want to get one :S

See if you can borrow another timing light also. If you have a white spark, the timing light should pick it up.

Kind of a side note, but might be relevant- I had gone through the wiring when I was putting the bike back together, and the regulator power had actually melted at the "bullet" connection so I cut, checked and re-connected the wire using a wire connector & heat sealed the connector. I'll be picking up the voltmeter, but maybe my coils aren't getting enough juice for the timing light to recognize a spark and it's because the regulator is faulty? Plus I think it's the only electrical component I haven't replaced yet.

If my regulator is bad, how would I check? And what kind should I get to replace the stock one with the setup I currently have?

Connectors usually melt due to increased resistance caused by corrosion. If your regulator is not regulating, it usually starts blowing bulbs because the voltage is too high.
It is good to hear that you went through your harness already, that is one step accomplished.
If you are not getting enough voltage, that is normally an indication of the rectifier/stator not inputting enough AC voltage. While it is possible that the regulator side could experience a diode failure, causing low voltage, the likelihood is low.
In any case, you absolutely must get a multimeter and check out both the stator AC voltage and regulator DC voltage.

emptypond wrote: If my regulator is bad, how would I check?

You use the DC voltmeter in your multimeter. Patton or 650ed probably have a link to a test document. Basically, you check DC voltages at various engine speeds.

emptypond wrote: And what kind should I get to replace the stock one with the setup I currently have?

This question is the subject of an entire thread, which I have not introduced in this forum. There is a new type on the market which is much improved over our shunt-style regulators.

emptypond wrote: If my regulator is bad, how would I check? And what kind should I get to replace the stock one with the setup I currently have?

It is important to know which model bike your engine is from because not all 1983 KZ750 models used the same charging system parts. Here are the 1983 KZ750 models; do you know which one you engine is from? Ed

KZ750-F1 (LTD Shaft) (1983)
KZ750-H4 (LTD) (1983)
KZ750-K1 (LTD Belt) (1983) (2 cylinder)
KZ750-L3 (1983)
KZ750-N2 (Spectre) (1983)

I believe it's an N or spectre. It's not shaft nor 2 cylinder... I'll get the voltmeter this evening and see what I can come up with.

Stator- low ohms with each pair of connection, but jumpy, sometimes read above 100...
battery- 12.7 (probably need a new battery, but I just bought this one 3 days ago)
I couldn't find clear instructions as to how to test the regulator.
I'm having a difficult time testing the coils. I'm thinking the sparks are yellow, and not bright white, as opposed to what I said last night, thinking they were actually white.

Your battery voltage is fine when off.

Run this Quick Test for the output voltage of your regulator. If you pass this, your charging system is fine.

Run the Coil Test part of this document to test your coils.