1979 MKii No workie...

I think you might need a battery. That might be enough to make the ignition falter, but I'm not sure on that. I know that mine would break-up and not run very well at all with a bad battery. I would start with a new battery or charge your old one and check your voltages again. The battery needs to hold a charge of over 12 volts when the bike is not running. Maybe someone else can confirm if the battery could cause ignition problems.

I can say for sure though that with only 9 volts at the coils you are not getting a strong spark, if any at all. Can you post a picture of the "box" that the wires run through? It sounds like that might be the resistor, and if so, you need to remove that with those coils. There is a great article on here somewhere on Wired George's coil modification. That is a great way to make sure you get a full 12v at the coil.

Your pick up coils look good. One of mine was "open" and didn't create any spark on 2 cylinders. Anyway, in the mean time, you can check the IC igniter with your meter. I'll attach a picture of the chart below. Make sure you click on the picture to expand it or you'll never be able to read it.

Well, I have the same 1979 MKII engine. It also
backfired and belched smoke.

The cure....

See those two rubber hose's comming off the front
cam shaft cover? Well remove them and then remove
the two plates. Inside you will find a pair of reed
valves on each side. They will be all nasty and not
doing thier jobs.

I made mine so they cannot operate. In any event
put the reed valves and valve cover plates back on
and connect a rubber hose from the left side to the
right side.

Some where near the coils you should see a smog
valve which likely no longer works. The two hose's
used to connect to it. (the ones you removed earlier).

Follow the vacuum line that comes out of the smog
valve till you find which carb it is hook to. Unhook
it and plug the port going into the carb.

Start your bike and readjust all the things you messed
with trying to find the problem.

The bike should now run WAY better. No more back
fireing.

Now you can remove the smog valve and hoses and store
them in a box somewhere.

Someone makes new covers for the valve covers that
no longer have a hose attachment point. It looks a
lot better. I made my own out of 3/16 alum.

Try the above...you'll love it.

Bob

Bob,

thanks for the tip on the reeds, but I already have them tied together as seen in the picture below.


Here is the box that wires go into. As you can see it is located directly below the coils.


Jason

Yea, that white box is a resistor and should be removed. That is cutting your voltage at the coils. It is needed for the stock coils but not with 3 ohm Dynas. Get that thing off of there and charge your battery. You might be OK if everything else checks out alright. Your probably don't even have enough voltage at the coils to generate a spark.

So, should I just follow wg's site to get that thing outta there?

I will take a look at george's site and see what is up.

I really hope this takes care of it.

Thanks.
Jason

I have not yet started up the bike yet, but I did get the relay in place and wanted to double check my work.

I hooked up the power and ground with no issues. The trigger wire and the power to the coils wire is the one that I am confused about.

There was a red wire that came from the controls on the handle bars and that went into one side of the resistor while the pink wire that came out the other side went to the coils. I checked the red wire and with the key on it gets a straight 12V. My question is why use the relay if this is already a switched power source with a straight twelve voilts.

Also, can I use this red wire to operate the relay?

Thanks guys, so close I hopefully can smell it.

Jason

Yes, you can use the red to trigger the coil. That way the kill switch on the handlebar will still kill the motor by killing the ignition coils. The red wire might be reading 12v now, but that wire goes up through the harness, through the kill switch, etc... could definitely loose some voltage at times. The direct to the battery route is best. If not, just removing that resistor will really help too. You loose voltage across the resistor to protect your stock ignition/coils, but don't need it with the 3 ohm dynas. Good luck!!

So, I checked all my voltages with the key on. Went over everything with a fine tooth comb. Still, no spark.

And, by no spark, I mean nada...nothing...zero.

Actually, I saw a good spark one time: That's right, one time.

So, I am going to recheck all the wiring and investigate grounds. I am going to disconnect all the wiring, clean all the connections, and re-attach it.

I am not sure what else to check. Is there any way to confirm that the pickup coil is working properly?

If the ohm resistances check out for the coils, could they still be bad?

What sends the signal to the coils to fire?

Jason

That's a bummer

The pick up coils send a signal to the IC igniter which sends a signal to the coils. Did you go through all of the igniter tests? I've never seen a bad pick up coil that measures good. If you're getting a good supply (12volts), a signal (from IC igniter) and have the spark plug grounded properly when you're checking, you should have spark. Is the plug grounded for sure when you're checking? You have to have the threads or the ground electrode touching a good ground. Sorry if you already know this, just want to make sure

Maybe there's a way to check the pick up coils with a light or volt meter, like you would with points?? If you turn your engine by hand maybe you could pick up a voltage at the black or green wire when the rotor passed through the coil field??

Maybe someone else can help us out.

OK then....

Cut that crossover hose in half and plug each half
with something.

Then... when you get done replacing the entire
electrical system and start getting fire to the
plugs.... it should run fine, (after you plug the
hose). Otherwise its gonna feed air and or exhaust
from left to right and right to left.

I went through everything you are going through
except I overhauled the carbs myself (lots cheaper).
My carbs are 31mm Mikuni's. Most KZ1000's were only
29mm. (factory installed).

Mine also sputtered and popped and shot flames and
white smoke till I plugged those hoses.

I had the high idle problem too... turned out I had
the idle adjust between carbs two and three set too
high. For some reason its very touchy to set. I idle
at about 900+ rpms now.

Good Luck....and remember, you didn't have ignition
problems till you started messing with the ignition
wires and stuff. Maybe you should put it back like it
was for now. My 79 KZ1000 has run just fine for 29
years without needing any relays or any such nonsense.

Let us know how it goes...
Bob

Bob_79KZ wrote:

OK then....

...
Good Luck....and remember, you didn't have ignition
problems till you started messing with the ignition
wires and stuff. Maybe you should put it back like it
was for now. My 79 KZ1000 has run just fine for 29
years without needing any relays or any such nonsense.

Let us know how it goes...
Bob

Bob - monkonmonk didn't mess with the ignition until he realized that he didn't have spark on 3 cylinders. That issue has to be corrected first, regardless of what you do with the suction valves or carbs or anything else. We have to have spark on all 4 cylinders.

As far as wired george's coil relay mod, it usually won't make the difference of the bike starting or not starting, but it does help performance. Monkonmond was only getting 9 volts to his 3.0 ohm dynas, and that is very bad.

I've never heard of having to plug the suction valves separately. The valves are basically a check valve that will only allow air to flow INTO the engine, not out of the engine. Unless you removed your valves under the covers, or unless they are toast, there is no way to "feed air and or exhaust from left to right and right to left". Even if the hose is a problem, that's something monkonmonk can look at AFTER the spark issue is corrected.

There is no way to properly tune, adjust or diagnose and engine running on 1 cylinder. Take a deep breath and relax, OK?

Monk's first post was, in part:
" When I first start the bike, the choke causes the rpms to rise to 3500rpms or so and then immediately come down to 2200 or so. If I take the choke off the bike will idle at around 900rpm or so. Then, mostly anything except gentle throttle causes the bike to die.

- The #3, I think (inner on right side), exhaust gets extremely hot while the others remained cool to the touch.

- The bike tends to back fire(flames shooting out and all) and sputtering lots of white smoke."

OK... I took a deep breath and pulled my shorts out
of my ass:P ....But...

It seems to me that everything you guys are having him
do is making it worse, and worse.

Now I'm not saying I'm right 100% of the time. But I
went through what he is going through exactly. In fact
a motorcycle mechanic gave up trying to figure my
problem out.

I found the solution here on KZR about a year ago. It
all was caused by the smog crap.

And yes, if the reed valves are shot...and they likely
are, exhaust and air WILL feed between the cylinders.
Number 3 cylinder is getting hot because the reed valve
for that one cylinder may be working...but barely.

Now it has escalated into a lot of needless expense
for the poor guy.

You guys gotta use the K.I.S.S. theory more often and
quit trying to sell everyone new and expensive coil and
relay gadgets. Mine will do over 100 MPH on stock coils.
That's good enough for all but drag racers.

No, I'm not being a smart ass. I'm actually trying to
help.

Good luck, I'm going riding..

Bob