kz750 no spark?

I replaced bad ignition coil but now I have no spark. Everything is testing fine except one side of dyna s ignition is low ohms. Any help would be much appreciated. Thank you in advance.

kwnics wrote: I replaced bad ignition coil but now I have no spark. Everything is testing fine except one side of dyna s ignition is low ohms. Any help would be much appreciated. Thank you in advance.

Is there full battery voltage at each ignition coil primary terminal?

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I believe so...is there a way to test?

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Do I have to have charged battery? And will this test work with multimeter

Okay I have 12v going to coils now only 1 and 4 are sparking?

kwnics wrote: Okay I have 12v going to coils now only 1 and 4 are sparking?

Does this mean that the two outside spark plugs #1 and #4 are sparking (with their plug wires connected to the same ignition coil), and that the two inside spark plugs #2 and #3 are not sparking (with their plug wires connected to the other ignition coil)?

What ignition coils are fitted (stock; Dyna; other)?

What spark plug wires are fitted (stock; Dyna; other)?

To aid diagnosis, could swap wires from Dyna-S between ignition coils to see whether only 2 and 3 are then sparking.

If not already done, could re-test for spark, using new spark plugs, or swap the spark plugs around to see whether it makes any difference as to which plugs spark.

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Stock ignition coils with dyna s ignition pickups. Yes 1&4 are running to one coil and 2&3 are running to the other coil. I will run the switching wires test tomorrow.

There is 4 brand new spark plugs and the wires are testing good.

Okay ran test with switching wires between dyna s and had spark on the other two with no spark on original so does that mean its the ignition pickup? Thank for all the help!!

Did the bike originally have points? If not, then you may eventually burn out the Dyna S when using stock coils. Dynatek says 3.0 ohms is the minimum resistance for coils used with the Dyna S.

The dyna was on there when I bought it. My coils read around 3 ohms resistance. Will bike still run with only 2 plugs sparking. And can I run both coils off one wire from dyna or will that mess things up?

kwnics wrote: The dyna was on there when I bought it. My coils read around 3 ohms resistance. Will bike still run with only 2 plugs sparking. And can I run both coils off one wire from dyna or will that mess things up?

Will bike still run with only 2 plugs sparking -- Yes, usually, but not very well, and probably barely good enough to out-run an older Harley.

can I run both coils off one wire from dyna -- No

or will that mess things up? -- Yes

Each ignition coil has its own independent "secondary loop" including the secondary winding, both plug wires, plug cap on each plug, the spark plugs themselves, and the metal engine head.





Lost conductivity in the secondary loop disallows spark on both plugs within the loop.

For example, a faulty connection between a plug wire and cap could cause a "break" in the secondary loop.

Has the non-firing secondary loop been ohm-tested between the caps to determine whether there is a "break" within the loop?

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