TOPIC:

Huh. So it appears the blue wire has nothing to do with the extra wire on the Zr400/550, as those bikes get a tach signal from the coil.

So the extra wire on those bikes is still a mystery. It would be nice to know what that wire does on those bikes.

Alright, I have a tuning session scheduled for the 21st. Looking forward to it and I'll post results after.

Question - think I could swap the green/black interlock wire for the black/yellow wire to provide ground to the igniter and restore the kickstand safety feature? I wouldn't worry about it if I were great about making sure the kickstand is up before taking off...but I space it occasionally.

Zaddict wrote: Question - think I could swap the green/black interlock wire for the black/yellow wire to provide ground to the igniter and restore the kickstand safety feature? I wouldn't worry about it if I were great about making sure the kickstand is up before taking off...but I space it occasionally.

I highly advise against that. The output driver of the igniter is almost always designed with a bleed-off circuit for when the coil's induced flyback voltage is too high for the driver to handle. The bleed-off path is to ground. If you remove that safety path by removing the ground you will force excessive voltage on the control circuit. This is likely why Kz igniters use a separate interlock wire rather than removing the igniter's ground.

A much better idea would be to use a relay to remove the power source to the coils. The relay should also include a diode to dissipate any induced voltage when the relay tries to open the circuit.

loudhvx wrote:

Zaddict wrote: Question - think I could swap the green/black interlock wire for the black/yellow wire to provide ground to the igniter and restore the kickstand safety feature? I wouldn't worry about it if I were great about making sure the kickstand is up before taking off...but I space it occasionally.

I highly advise against that. The output driver of the igniter is almost always designed with a bleed-off circuit for when the coil's induced flyback voltage is too high for the driver to handle. The bleed-off path is to ground. If you remove that safety path by removing the ground you will force excessive voltage on the control circuit. This is likely why Kz igniters use a separate interlock wire rather than removing the igniter's ground.

A much better idea would be to use a relay to remove the power source to the coils. The relay should also include a diode to dissipate any induced voltage when the relay tries to open the circuit.

Ah, well that's very good to know, thanks for the warning! I was wondering why the igniters seem to have 2 grounds. I could set up a relay to remove the power to coils easily enough. You think that would be preferable to interrupting power to the igniter? I'm not sure how I'd use a diode to dissipate induced voltage. My understanding of diodes is they're like one way valves for current - where would it go and in which direction?

The problem is in turning off the ignition without causing a backfire, and/or arcing the contacts of the relay.

There are several options.
One is to live with the chance of a backfire. This would be the simplest option. You would simply wire a relay so that the neutral switch and kickstand switch were in parallel. As long as either one is made, the relay stays energized and power is routed to the coils. The kickstand switch would be closed whenever the kickstand is up. If the kickstand is down, then the neutral switch must be closed (trans in neutral). In order for the neutral light to function normally, a diode would be required, but I assume you would be using the normal interlock wire which already has diodes in place. The only question is if the diode block can handle enough power to power the relay. I would think it can. It will take about 1/4 amp.

Another option is wire the relay so the contacts interrupt the pickup signal. I'm not sure what this would do regarding backfires. I personally don't like the idea of having something in the pickup wire path in case it induces noise or some other interference.

A third option is to wire the relay as in the first option, but use a heavy duty, 25 or 50v Zener diode in parallel with the relay contacts... probably 2 watt or higher if you can get it. A zener is what is typically used as that aforementioned safety valve to protect the output driver. But in this case the voltage will be selected much lower (they are usually rated in the 300 to 400 volt range to protect the driver) so that a spark will hopefully not occur when the relay opens.

The same drawing can be used for option 1 or 3. You just leave off the part labeled "Z1".
The kickstand switch, neutral switch, and diode are shown for reference. They are not necessarily how your bike is wired, but is how one would wire it from scratch if they had to. You would just connect your interlock wire to the D1 and pin 86 junction.

Here's a link to the Zener diode (Z1). It's about 50 cents each. You might want to get a couple if you have that kind of cash available.
The other diode "D1" can be found at digikey also. It's a very common part. If Radio Shack was around, they would have had it.
D1 can be a 1N4001 or 1N4002 or 1N4003 etc. The specs are slightly different, but won't matter in this application.
1N5368BRLG
www.digikey.com/product-detail/en/on-sem...68BRLGOSCT-ND/893871

loudhvx wrote: The problem is in turning off the ignition without causing a backfire, and/or arcing the contacts of the relay.

There are several options.
One is to live with the chance of a backfire. This would be the simplest option. You would simply wire a relay so that the neutral switch and kickstand switch were in parallel. As long as either one is made, the relay stays energized and power is routed to the coils. The kickstand switch would be closed whenever the kickstand is up. If the kickstand is down, then the neutral switch must be closed (trans in neutral). In order for the neutral light to function normally, a diode would be required, but I assume you would be using the normal interlock wire which already has diodes in place. The only question is if the diode block can handle enough power to power the relay. I would think it can. It will take about 1/4 amp.

Another option is wire the relay so the contacts interrupt the pickup signal. I'm not sure what this would do regarding backfires. I personally don't like the idea of having something in the pickup wire path in case it induces noise or some other interference.

A third option is to wire the relay as in the first option, but use a heavy duty, 25 or 50v Zener diode in parallel with the relay contacts... probably 2 watt or higher if you can get it. A zener is what is typically used as that aforementioned safety valve to protect the output driver. But in this case the voltage will be selected much lower (they are usually rated in the 300 to 400 volt range to protect the driver) so that a spark will hopefully not occur when the relay opens.

The same drawing can be used for option 1 or 3. You just leave off the part labeled "Z1".
The kickstand switch, neutral switch, and diode are shown for reference. They are not necessarily how your bike is wired, but is how one would wire it from scratch if they had to. You would just connect your interlock wire to the D1 and pin 86 junction.

Here's a link to the Zener diode (Z1). It's about 50 cents each. You might want to get a couple if you have that kind of cash available.
The other diode "D1" can be found at digikey also. It's a very common part. If Radio Shack was around, they would have had it.
D1 can be a 1N4001 or 1N4002 or 1N4003 etc. The specs are slightly different, but won't matter in this application.
1N5368BRLG
www.digikey.com/product-detail/en/on-sem...68BRLGOSCT-ND/893871

This is amazing.  I'll give option #3 a shot.  Thanks very much Lou!

OK, I'm finally getting around to installing the kickstand safety switch relay Lou designed. I have one point of confusion - should I be interrupting power to the igniter or between the igniter and the coils? I'm assuming it's the latter but want to double check.

The relay only interrupts the power to the coils. Power to the igniter stays on.

Oh wait, is it the power from the kill switch circuit to the coils that I should be interrupting? I think makes more sense than what I was imagining.

The kill switch most likely powers the igniter and the coils. I am suggesting interrupting the branch that feeds the coils only. I think I would tap in right at the coils. On Kz's, that's an easy to access area. I'm not sure what the terrain looks like around the coils on the Zr.

You're right, looks like the power from the kill switch is connected to both ignition coils as well as to the igniter (red wire in the diagram).
But what other "power to the coils" is there? I see a green lead from the igniter to what looks like just the 3-2 coil (not the 1-4 coil). Then there's a black lead that connects to the just the 1-4 coil (but not the 3-2 coil), as well as to the tach. But shouldn't those then be grounds? I'm just trying to understand how the system works. I'm thinking the igniter is alternately opening and closing the circuits to the coils through the green and black wires. I don't see where the relay would fit in. Or is it that I would keep power (through the red wire) going to the igniter, but then connect the coils to that same power through the relay? So that would involve putting the relay right at that branch point where the coils are getting power from that same stop switch circuit that is feeding the igniter (but keeping power to the igniter in tact)?

Coils get power from a common source that stays on all the time as long as the ignition switch and kill switch are turned on. That is the positive side of the coils.

Each coil also has a negative side and that connection is either green or black, and those two wires are controlled by the igniter. Yes, they alternate between being open and shorted to ground through the igniter. (When they are open, they should read somewhere near 12v.)

The positive connection to each coil comes from the harness from some common point. Usually, that one common point is visible somewhere near the physical location of the coils. I am suggesting to break the circuit with the relay just before that common point. That will remove power from the coils just the same as opening the kill switch.

On your diagram, that common point would be just to the left of the two red lines going to the coils.

You would physically break (cut) that spot on the red wire and the two loose ends go to the relay.
On my diagram, those two loose ends are called something like "switched 12v power for coils" and "to positive side of both coils".

The igniter can stay powered on as that should not matter, thus it stays wired as is.