coil mod for KZ550C3

So I'm probably the millionth person to post with coil mod relay questions... what do I win?

In all seriousness, I'm going to make this happen, hopefully this weekend. Background: I have an '82 KZ550C3, electronic iggy. Coil resistance is out of spec but okay, 2.8 and 2.9 primary, respectively (Clymer sez it needs to be 1.5, you guys tell me that stock is 2.5 and I believe you). Last I checked, I get about 12.6 volts at the battery and 11.8 at the coils - not horrible, but certainly a measurable drop. Some questions...

(1) While browsing through the old forums, I saw that someone had a wiring diagram that showed a five-prong relay (two 87 prongs), with one 87 prong powering the coils, and the other going to the IC ignitor and then ground. Is this necessary, or should I just go for the mod as written up by WG and not touch the ignitor circuit?

(2) Can someone take some pics of the installation, especially the way the pigtail hooks up to the trigger wire (yellow/red on my bike) and of the connectors on the power wire to the coils? I was thinking of just taking the connectors off of the red/yellow trigger wires and using those to connect the coils to the power wire in the same setup. Then I guess I'd just need a connector for getting a wire from the pigtail to the trigger (assuming I'd use a connector here and not hard-wire it in). So in general, a pic or perhaps a different description of setting up the trigger wire to the pigtail and the entire new coil power wire would be helpful.

I don't expect this to solve my current problems (#3 won't fire at startup but eventually gets going when warm), but I hope it'll at least get me a better spark, which will allow me to tune the bike better and take one more thing off the list o' things to check.

Thanks in advance!
Nick

Nick, my voltage readings were very similar to yours and for the extra 1/2 volt gained by doing the mod there was an improvement in performance.

The original WG write up was designed for a motor running the old fashioned points. You, like me have the electronic ignition so you have to include the igniter. Take a look at my post from last year. I hope the diagrams I put there will help.
kzrider.com/component/option,com_joomlab...ew/catid,4/id,53755/

Dont think I have and photos but will look.

Good luck with the mod

OK
Photos.
First is a pic of the wiring before doing the mod. Took off the tank and had to carefully slice open the harness.

All the red wires in the pic are labelled. All come together at the point labelled "soldered junction".

The one labelled "from kill switch" was cut and the upper wire connected to black or 86 on the pigtail.
The lower part of the cut wire was run/connected to yellow and 87 on the pigtail.

All connections I made were soldered and covered in shrink wrap.

See following pics.

Post edited by: JR, at: 2007/07/05 14:27

Post edited by: JR, at: 2007/07/05 16:14

The relay and pigtail is bolted to the frame just forward of the battery. I have the space since I use pods.

I unbolted the relay and turned the pigtail upside down for a photo. May not be to clear.
The pigtail came with wires attached.
The white becomes green and is bolted the crankcase for ground. The white end connects to 85.
The blue is connected to 30 and then runs via an inline fise to a power point - next pic

You can see the black from Kill and yellow trigger mentioned already.

The center pin on my relay is number 87A and I dont use it.

Post edited by: JR, at: 2007/07/06 08:47

Last pic follows the blue wire from 30 on the relay through that black tube containing an inline fuse and bolted to the live end of the starter solenoid. I had to open the cover of my fuse box to be able to show the setup. I still need to replace this piece with a blade fuse setup... the shame .

Hope all this helps



Post edited by: JR, at: 2007/07/05 14:27

Post edited by: JR, at: 2007/07/06 08:48

JR - Would the power into the relay wire with the fuse be #30 and not #80?

wiredgeorge wrote:

JR - Would the power into the relay wire with the fuse be #30 and not #80?

You know George you could be right. With my eyesight I possibly mistook "3" for "8" .

Yep. You are right. I checked and corrected / edited the posts above. Hope I hav'net sent anyone off in the wrond direction.

Post edited by: JR, at: 2007/07/06 08:49

Great pics & description, this is just what I needed. Thanks!

Gonna hit up the local Radio Shack this afternoon and pick up the rest of the components I need (though I guess I may need to hit an auto parts store for the relay & pigtail; we'll see). With any luck I can put everything together tonight or tomorrow.

So as I understand it, the only connectors I need to purchase are the "eye" type connectors for the ground & power, correct? Or, in the interests of completeness, do you recommend I get a few other connectors to connect the trigger wire to the relay and another for the igniter to the relay? That way, I suppose, if I ever had to replace the relay or igniter, it wouldn't involve cutting... any thoughts?

I was also just planning to go with the inline fuse, any particular reason you'd prefer a blade-type?

I still have the stock airbox, so I may be searching for a good spot for the relay. Was thinking under the battery box or perhaps hidden under the side cover somewhere.

Thanks again for the help & pics, this is great.

I just did this mod last week on my 650 C-1. You might want to save yourself some grief and aggravation and just order your relay and pigtail from the place George has linked from his website. I tried the local auto parts store and just ended up getting pist off. Also all the relays they were showing me had no bolt hole to attach them and cost anywhere from $12 to $20.

nick
You will probably find an assortment pack of connectors at Radio Shack. I'd suggest you get some heat shrink tubing to cover the connections while you are at it. People use different kinds of connectors. I dont think there is any rule. I prefer to solder but that's just me. I bought the old style inline fuse holder simply because it was there on the shelf. The newer blade type fuses are easier to find. you can likely get them at any filling station. At some point in the future I intend to uprade all fuses to blade type

Gringo
I can get those Bosch automotive relays and pigtails at a surplus store in Kitchener which is about 50km up the road. I think they cost me about $6CDN total for pigtail and relay. Just happened to be in browsing one day and bought.

This is a picture of how I mounted my Coil Re-powering Relay (K1) under the left side cover:



Note that the loose fitting Tie-Wrap isolates the Coil Relay from vibration and is easy to move or replace.

Also, note that the small Tie-Wrap around the Relay and Relay Socket keeps them from separating due to shock and vibration.

Best of success.

Post edited by: bill_wilcox100, at: 2007/07/06 10:29

Post edited by: bill_wilcox100, at: 2007/07/06 10:32

Post edited by: bill_wilcox100, at: 2007/07/06 12:56