Zephyr 750 Ignition Swap

Thought I'd post this here as I couldn't find anything definitve when I searched last week. 

I have been building a '93 zephyr with my son and due to the changes made to the front end we used a KZ1000A ignition switch and steering lock. We ran into problems when trying to start the bike as the original switch has a resistor in it that is used to drop the voltage on one of the wires to the ignitor - making it harder to hotwire I suppose. We figured this out and got the bike running but ran into the same problem again and couldn't get it to work properly (maybe the battery voltage was too low?). We decided to get an aftermarket ignition to cut out the ignitor altogether and simplify the circuit. 
As there are no aftermarket options for the Zephyr we looked at the options for the KZ750. I tried out my KZ750H ignition today and it works perfectly, the aftermarket one was fine as well. The Zephyr uses a KZ750 crank that was introduced mid-year on the '82 models. I wasn't sure about the fittings on the crankcase but they are the in the same position and at the same offset as the KZ750.
Just thought I would document this in case anybody is looking at replacing the zephyr ignition system.

On a side note, I accidently shorted the 750 ignitor (don't ask!) and a decent amount of smoke came out of all the wiring. It still works fine but I'm not sure I can trust it. Keep using it or ditch it and get a replacement?

Hi Calum, I ran into this years ago with a later model Kawa (think it was an early ZX10) it is indeed an anti-theft device. I believe the ignition module is looking for no more than 9v. You could use a variable resistor to dial in the correct amount of resistance then once you know the value simply fit a fixed resistor in the supply line to the ignition module (BE CAREFUL WHERE YOU MOUNT IT AS IT WILL GET HOT AND MAKE SURE IT IS SUITABLE FOR THE CURRENT DRAW OF THE MODULE)
Ref the smoke carefully inspect the insulation on the wiring, it probably looked worse than it was. Generally electronics are pretty fragile so if the module is still working it is likely to continue to do so.

I have looked at the wiring and it looks OK. Just didn't want anything catching on fire later down the line
The aftermarket ignition (similar to a dyna s) is installed and gave us a bit more room with the wiring so we'll be leaving it in. 

wrote:

I have looked at the wiring and it looks OK. Just didn't want anything catching on fire later down the line
The aftermarket ignition (similar to a dyna s) is installed and gave us a bit more room with the wiring so we'll be leaving it in. 

Sounds like a plan, I didn't realise how far down the road you were with the conversion. sounds like you have it covered

Yeah, this was really just to put the information out there that the crank and crankcase on the Zephyr will take the older ignition systems. Might make it easier for someone else working on a Zephyr. The 9V limit is good to know - I think we ended up using a 100 Ohm resistor, that number should have probably been a bit higher.

[EDIT: I also assume that there would be basically no current running through this circuit as it's not actually part of the ignition system - was I wrong?]

wrote:

Yeah, this was really just to put the information out there that the crank and crankcase on the Zephyr will take the older ignition systems. Might make it easier for someone else working on a Zephyr. The 9V limit is good to know - I think we ended up using a 100 Ohm resistor, that number should have probably been a bit higher.

[EDIT: I also assume that there would be basically no current running through this circuit as it's not actually part of the ignition system - was I wrong?]

There would be current but only minimal, the main feed for the igniter is a brown from the fuse box. The resistor is in a light grey wire from the ignition switch to the igniter (this is just an input to tell the igniter the ignition switch is on and not by-passed) I believe all Kawasaki of that period had this system

100 Ohm will do it.