Intermittent spark

Hello all, 
I just bought a Kawasaki gt550 g7, and i am experiencing intermittent spark. It goes for a few minutes then dies, sometimes i can start it up right again but it dies rather quickly, other times i get no spark even when its been standing for a while. Ignition coils read good and i have even tried other ones, same problem, new plugs new caps. Pickups resistance is measuring in spec even when i have no spark. I am getting fluctuations when measuring volt on the pickups and cranking so it seems like they are generating a pulse, i dont know if those readings are in spec or if my multimeter is even fast enough to react and measure the pulses. I have cleaned every connection and every earth point seems to be tight and good. The fuse box also seems solid. Its sounding like an Ic igniter problem maybe but i want to be sure before i go and spend money, can you know for sure or do i have to take gamble and source a new igniter? 
Thankful for any suggestions
 

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SvansLös wrote:

Hello all, 
I just bought a Kawasaki gt550 g7, and i am experiencing intermittent spark. It goes for a few minutes then dies, sometimes i can start it up right again but it dies rather quickly, other times i get no spark even when its been standing for a while. Ignition coils read good and i have even tried other ones, same problem, new plugs new caps. Pickups resistance is measuring in spec even when i have no spark. I am getting fluctuations when measuring volt on the pickups and cranking so it seems like they are generating a pulse, i dont know if those readings are in spec or if my multimeter is even fast enough to react and measure the pulses. (you can only accurately measure the pulse with an oscilloscope)   I have cleaned every connection and every earth point seems to be tight and good. The fuse box also seems solid. Its sounding like an Ic igniter problem maybe but i want to be sure before i go and spend money, can you know for sure or do i have to take gamble and source a new igniter? 
Thankful for any suggestions

 

What is the voltage at the feed side of the coils when cranking (ideally when it won't start) ? you can test the IC igniter output by connecting an LED across the coil connections (polarity sensitive) when cranking the engine or when running the LED should pulse as the coils are triggered.

I have stuck a probe on the backside of the negative terminal on the coils so its still connected, it hade battery voltage when cranking, this side should ground on and of right? So it should not be battery voltage?

SvansLös wrote:

I have stuck a probe on the backside of the negative terminal on the coils so its still connected, it hade battery voltage when cranking, this side should ground on and of right? So it should not be battery voltage? It will show battery voltage when the ground is "off"

When you say a "probe" what do you mean ? unless it's an LED test probe it probably won't react fast enough to be conclusive, however constant battery voltage on the negative (switched side) of the coil points to a defective IC igniter or an open circuit in the black and green trigger wires between the coils and the igniter.
If you disconnect the negative wire from the coil and use a piece of wire to ground the coil negative for a few seconds do you get a spark when you remove the ground ?

Yes a multimeter probe, i suspected it would be inconclusive with triggers, but i can see battery voltage and the startmotor draining lowering the voltage. By grounding the the negative side and removing whag am i testing? The trigger wires?
 

SvansLös wrote:

Yes a multimeter probe, i suspected it would be inconclusive with triggers, but i can see battery voltage and the startmotor draining lowering the voltage. By grounding the the negative side and removing whag am i testing? The trigger wires?

 

If the HT lead and spark plug are resting on the top of the engine with the ignition on, if you give and remove ground from the coil negative terminal you should see a spark on the plug. This is testing the electrical circuit and switches up to and including the coil.
If this test shows a spark then your issue is in the igniter, pick-up coils or the wiring from the coils to igniter and pick ups.

I am not getting spark at the plug i am getting spark where i connect and remove ground
thank you

Hello 
I have a kz550 gt G7, and have been thinking about converting it to something like a dynatek ignition system. Of course my bike as the electronic timing advancer and not the mechanical, so i would have to put a  mechanical advancer from earlier years same model in my bike. Does anyone know if this would work? I was also wondering if anyone has any experience with knockoff "dynatek" like the kz550 kit from amotoparts. 
thank you!

Have you checked both primary and secondary winding resistance and also checked for continuity between both primary and secondary and the mounting post - all you are doing with the ground is simulating the igniter (have you disconnected the black and green wires from the coils before applying the ground) also is the plug shell grounded on the engine ?

lot's of people here are running the copy dyna S systems with mechanical advancer

Is everything on the bike stock?

Ok, let's figure this out.
Grab your volt meter.
Put your meter on DC V.

Turn the KEY ON.
Kill switch set to RUN
Try to start the bike.
If the bike starts, let it run till it dies.
We can't find the problem if the bike is running ok.

When the bike won't start.. leave the KEY ON
kill switch set to RUN

red probe on positive battery post(post is the metal part of the battery)
black probe on negative battery post
What is your voltage to the tenth decimal place (12.3 instead of 12)

move your red probe to the yellow and black wire at the igniter connector
back probe that wire from the igniter side(do not disconnect the connector)
what is your voltage?
Voltage should be as close to 0.0v as possible.
Any higher than 0.5 then your ground connection isn't very good. 

Move that red probe to any metal part of the engine block.
All points that are metal on the block should be 0.0v

Move the red probe to the green wire at the coil.
What is your voltage?

Red probe to the black wire on the other coil
What is your voltage?

Move your black probe to the positive battery post.

Put your red probe on the yellow/red wire at the igniter connector.
Back probe the wire from the igniter side.
What is your voltage?
Should be close to 0.0v

move your red probe to the yellow/red wire at each coil.
What is your voltage?
should be 0.0v

turn off key