coil question

I recently bought a trashed kz1000 1979 shafty. All the wireing was screwed up. So I wanted to check and see if I could fire this thing up and I stripped all the wiring out. I put straight 12 volts to the coil on one side and left the ignition wires hooked up. It ran. I let it run for about 10 minutes and shut it off. I then started it back up and let it run. I then smelled something and it was the coils smoking. They seeped black goo and cracked. I shut it off then and have not started it since.I put the coils in the trash. This has been stored outside for 5 years. The question is do you think I fried the ignition for some unknown reason too? I hope not because it is a dyna ignition. By the way I am just going to use the motor for a spare and trash the rest because it is all in bad shape.

I doubt you fried your Dyna S, but the coils are deffinately pooched (obviously).

Coils really cant be asked to do too much efficiently after 5+years anyways.

You can check the dyna with a timing light / 12V light probe. Just put battery + to the dyna red wire, and - to ground. Connect your light to the coil output wire and ground then turn the crank. When the plug is supposed to fire (timing), the light will flash/go out.

Careful letting these old air cooled bikes idle for too long, as they can overheat and cause piston/ring damage if a lean condiion exists in 1 or more cylinders...

GL!

If you're going to be running the engine for extended periods of time like carb sync. a big fan can keep the heat from doing damage.

Coils can and do fail from overheating. Z1 sells replacement coils that should work.

terry s wrote:

...put straight 12 volts to the coil on one side and left the ignition wires hooked up. It ran. I let it run for about 10 minutes and shut it off. I then started it back up and let it run. I then smelled something and it was the coils smoking. They seeped black goo and cracked. I shut it off then and have not started it since.I put the coils in the trash. This has been stored outside for 5 years. The question is do you think I fried the ignition for some unknown reason too? I hope not because it is a dyna ignition. By the way I am just going to use the motor for a spare and trash the rest because it is all in bad shape.

Perhaps not the case in this instance, but should not leave the battery positive attached to coils while the engine isn't running, as this is same as leaving the ignition switch in the ON position while the bile is parked (which can fry the coils).

Also, Dyna-S ignition tends to heat up the coils more at lower rpm's (such as idling) than does the oem ignition.

Good Fortune!

I didn't wire the resister in the series when I did that. Could of that fried the coils? What exactly is that resister for? Does it drop the voltage down when the regulator kicks up? thanks

Leaving the ignition on without the bike running is bad, as Patton said. But even with the bike running, the Dyna S increases the duty cycle tremendously. This causes the coils tyo heat up more than they did in the stock setup. This can melt some coils.

If your coils were less than 3-ohms, and you did not have a resistor in the coil circuit, this also can melt some coils. The Dyna S has a rated 3-ohm minimum on coils. If your coils are a lot lower, there is a chance the Dyna S is damaged, but you won't really know til you get new coils.

The resistor limits the current in the coils to protect the coils and protect the ignition. (Even points will use a ballast resistor in some vehicles.)

Get 3-ohm coils if you are going to stick with the Dyna S, then you can eliminate the resistor.