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When all the smoke has escaped from inside the wires...
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Re: ZR550 Ignitor Info Request

12 Mar 2018, 00:51

Cory, you highlight a point that I suspected, but never proved years ago when I was figuring out how to integrate the zr550 wiring harness and ignition into my kz750.
I noticed that the keyway between the 550 and 750 rotors were indexed differently. More than the 1°total advance difference in timing between the two. When I was investigating these differences, my 750 motor was torn apart so I could't compare the TDC on the engine with the TDC marking on the timing rotors. I just decided to use the zr750 rotor and never thought about it again.
two rotors

But your post reminded me that I never tested the 550 rotor on a 750 engine. So I made a jig to compare the two rotors in a vaguely scientific manner. I printed out a degree wheel and attached it to board complete with a center pivot and a rollpin to fit into the keyway in order to index the two rotors in the exact same spot.

Since I arbitrarily placed the rollpin at 0° the zr550 TDC mark points roughly at a nonsensical 335°as I am only paying attention to the difference in degrees between the two TDC marks. ( It was hard to align the camera to capture the exact alignment between the TDC mark and the degree wheel.)

To be continued.......

Re: ZR550 Ignitor Info Request

12 Mar 2018, 01:41

The 750 rotor shows TDC to be 9-10° different at 345°

This shows the stock kz750 centrifugal advance rotor TDC lines up with the 345° mark showing that the 750 crank and locating pin is indexed 9.5~10° different than the 550.
stock 750

So a difference in crank stroke between the two motors may be the reason for the TDC index to not match between the two seemingly identical rotors. There is also a .5 of a degree difference in initial timing between the two rotors which would be impossible to see with the naked eye.
But the fact is that the ~10° difference between the rotors means they are not interchangeable between the two engines.

As for how the timing rotor works on the Zephyr's is kind of a mystery. None of the service manuals explain how they work, only how they can be diagnosed/serviced.
On the zx550's with dual pickups and a rotor with one single "bump", each pickup will tigger one coil as the rotor bump passes by. The Ignition module also measures the voltage pulse created by the bump passing by the pickup. The voltage pulse differs with the time it takes for the bump to pass by the pickup, thus giving the ignition module a way to measure the engine RPM's so it can adjust the ignition timing accordingly.
So the zx550 setup is pretty simple. Bump triggers one of the two coils, coil fires on two cylinders (wasting a spark on a cylinder that is on the exhaust stroke) and the pulse is measured to figured out what the rpm's are and adjusts the timing.

The Zephyr has only one pulse pickup and a rotor with four bumps. Which is super confusing to me, so all I can think of is:
So because there is only one pickup module, I think the smaller bumps are used to tell the ignition module every time a coil needs to fire and which coil it needs to fire. (again...one coil fires two different cylinders at the same time, wasting a spark on a cylinder that is on the compression stroke. Hence the wasted spark name.) And the larger bump serves to trigger a coil and also creates the voltage pulse that the ignition module needs to determine the RPM's. But I don't under stand why there isn't just two bumps 180° opposite from one another used to trigger the coils instead of four. So maybe the smaller bumps create a metronome effect that the ignition module uses to time the firing of the opposite coil 180° after the first one fires. I'm stumped.
Last edited by DaftRusty on 13 Mar 2018, 19:54, edited 2 times in total.

Re: ZR550 Ignitor Info Request

12 Mar 2018, 12:02

I think we need the CDI schematics to get this story developing further, I searched for it a few times without any luck. I wonder how digital it is in which case the extra bumps could be used to keep the CDI synchronized (better), if it's full analog then I need to see the schematics as well to reverse engineer to a conclusion as in why...

Re: ZR550 Ignitor Info Request

12 Mar 2018, 14:53

Wow! That is a lot of work, and very impressive. Good information.

I did buy a like-new Factory ZR550 Manual (3rd Edition) 99924-1136-03 that covers through 1997. There are 2 different part numbers for the igniter(90-91, and 92 -->), and there is a difference in the ignition timing, using the same pick up, and same rotor.

Zephyr Manual 2.jpg
Zephyr Manual 2.jpg (25.64 KiB) Viewed 1189 times
ZR550 Timing.JPG

Re: ZR550 Ignitor Info Request

12 Mar 2018, 17:56

My factory Kawasaki service manual does not show the information that yours does. But I have a Haynes manual that covers the US and UK bikes.
Your manual shows a error with the Haynes manual. (surprise surprise)
The UK bikes have a 13°idle and 36° full advance, not the US ones.
Screen Shot 2018-03-12 at 11.38.59 AM.png

The 1990 zr550 owners manual also confirms that the US has the 12.5° idle and 35° full advance.
Screen Shot 2018-03-12 at 11.50.51 AM.png
Owners manual

This information dosen't really help anyone, I just wanted to highlight the Haynes error.

Re: ZR550 Ignitor Info Request

12 Mar 2018, 18:45

I have been looking on Ebay for the Factory Manual that covers the full range of the ZR550 for a while now, as all I have seen is the 1st Edition ending in part number -01. When this 3rd edition came up, I scooped it up. The Factory Manual is good, but I have seen a few errors for the ZX550.

I sent a friend of mine a new, last edition, Kawasaki Base and Supplement Manuals from Kawasaki for the KZ/GPz550, and he had them scanned to 2 PDF Files cover to cover. Now we have this information accessible at anytime. Has this been done here, or thought of doing it with any of the ZR Manuals? Might help others looking for a manual for information.

This is what they look like:
KZ/GPz 550 Base Manual
KZ/GPz550 Supplement Manual

Re: ZR550 Ignitor Info Request

13 Mar 2018, 20:26

I have both of those manuals downloaded from somewhere on the web, but yours are of much higher quality! Thank you for providing those.

The Haynes version which covers the US and UK zr550 and zr750 is floating out there on the web. It's not the best but it is better than not having a manual at all.
Download here
I have never found the factory versions of either though. I always wanted to look through the zr750 FSM just to see what neat info it might have.

Re: ZR550 Ignitor Info Request

11 Jun 2018, 06:11

Looks like the two ignitors correspond to the zr550 and zr400. The input wiring is different. I'm trying to get a wiring diagram for a zr400 as I'd like to use an aftermarket ignitor designed for the zr400 (the SP2) in my 550.

zr550: 21119-1277
zr400: 21119-1313

Re: ZR550 Ignitor Info Request

12 Jun 2018, 03:20

92-93 ZR550 Uses the 21119-1313 igniter, according to Kawasaki.com
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