No spark at the plugs.

[Gary Papesh]

I’m hoping someone may have a suggestion regarding no spark at the plugs.
I’m putting my bike together after a rebuild, I’m stumped on the ignition. I have tested the coils, primary and secondary sides are within spec. The lower coil had bad wires, and 2 of the caps had high resistance. All 4 now have new 5 k NGK caps. The stator test on the pickup, and supply coil are both in spec. New battery, all fuses are good. Cleaned the battery box ground, and the battery terminals are clean.
The YPVS motor works as it should, neutral light works, oil light, high beam indicators are good. Headlight is on . Gauge lights are on.
I tested the kill switch for continuity, it’s good. Tested the side stand switch, it’s good. Tried to unplug the sidestand controller like the test in the manual states, no sparks yet. Unplugged the ignition switch, the red wire from the harness has 12 volts to supply the switch. There are 5 wires in the switch plug. I’m looking at the wiring diagram that looks sort of like a picture (the full color one that shows the shape of the connectors, and colors of the wires),the red and brown have continuity, and the blue/ white and red/ white have continuity when the switch is on
There is a darker color wire coming out of that plug, doesn’t really look black, but I’m assuming it’s a ground.
So based on this i believe the switch is good.
I thought the CDI might be bad, I put it on a buddy’s RZ 500, and it started right up, so that’s good.
I read in the electrical forums here that there is a white wire that goes to the tach that if not connected will stop it from running. I haven’t touched any of this, and all the wires look to be in place. Nothing hanging off.
According to the troubleshooting flowchart in the manual, my last step is replace the CDI, but since it’s proven to work, I’m out of ideas.
I know it’s archaic but if this thing had points and condenser, I’d be done by now
I set my multimeter for voltage, hooked the probes to the pickup wires coming out of the stator cover, turned the ignition switch on, and kicked it over.
I was expecting to see some voltage here or something. The resistance of the pickup is in spec, but shouldn’t this be sending out a “signal” of some sort as the magnet of the flywheel goes past it and then to the CDI?
Any ideas would be appreciated!

[steveho]

It seems the pick-up coil that senses the flywheel loses its internal magnetism over time.
The work-around is to reduce the gap between it and the flywheel ‘tabs’ to around 0.6-0.8mm.
I did this and got my sparks back (albeit seem weak as not super-bright blue, but sufficient for the engine to run).
A bit of ingenuity is needed to slot the mounting hole(s) and to achieve a gap measurement.
Good luck!

[Gary Papesh]

Thank you Steve, I will definitely try this!

[Jeff B]

When I had ignition issues it turned out to be bad ground.

[Gary Papesh]

Hey Jeff, are you referring to the grounding terminal at the battery box, or a different one?

[Gary Papesh]

Steve, I tightened up the clearance between the rotor and the pickup until it hit, then backed it up a bit. Unfortunately it didn’t help. I’ve got a new pickup on the way, hopefully that will do it.

[Jeff B]

It was many years ago so it's testing my memory a bit. I think the issue was ground between the engine and the frame or the frame and the coils. I think I added a ground wire somewhere. Maybe engine to rectifier or engine to coil mount. I can look at my bike tonight. See if it jogs my memory.

[steveho]

Steve, I tightened up the clearance between the rotor and the pickup until it hit, then backed it up a bit. Unfortunately it didn’t help. I’ve got a new pickup on the way, hopefully that will do it.

OK, but worth a try as has worked for some. Frustrating that you have to keep on searching for the cause of the problem. You’ll get there in the end! Maybe Jeff B is onto something with a ground issue. Good luck!

[Gary Papesh]

I did repaint the engine during the rebuild. I used DuPont Centari, which is an old school single stage enamel, and fairly thick. I’ll try a temporary wire from a bare bolt to the battery, I think that would prove that one way or the other.

[Jeff B]

I took a look at my bike. It didn't help. I don't remember how I fixed my ground issue.

[Gary Papesh]

Thanks for trying!