Ignition miss?

You may have seen in the new members forum that I just picked up this KZ.
Loving this bike but am having a bit of a miss that I need to track down. Sometimes its bad, other times not bad but always present and annoying.
I put a timing light on #1 and #4 (theyre the easiest to get to and are on separate coils) and at the moment of the miss the spark is cutting out completely. It seems to be doing it on both sides at the same time but not positive. I would have thought it was a bad coil but since its doing it on both sides Im guessing that both coils arent the problem. I know this isnt a lot of info but thought Id throw out what I know at the moment for maybe a little input from people more experienced that I with such a bike.

ANY input would be great.

Thanks and heres a pick of the patient.

Timing advancer might need lubed

Thanks.
Ill pull the cover off.
Will I know what you mean when I see the advancer?

Ive looked at the parts diagram and I do see the part but not sure what needs lubed ?

Very nice looking bike. You haven't given us much to work with here. Does it miss at idle, mid range full throttle. Does it get worse as the revs go up, does it ever clear up as throttle is applied, ect.

All moving parts on the mechanical advancer should have a light coat of grease(I use the high moly content grease), make note of how it's assembled, as it's possible to re-install it 180 degrees out, to verify correct assembly, start the engine, if it cranks & cranks, it's probably put together wrong.

baldy110 wrote: Very nice looking bike. You haven't given us much to work with here. Does it miss at idle, mid range full throttle. Does it get worse as the revs go up, does it ever clear up as throttle is applied, ect.

Thanks guys.

Yes it does it whenever it feels like it. No specific rpm range that I can tell. Even will do it at idle but not as often.
If I had to guess, more often at 1/4 throttle but thats possibly because thats were a lot of normal riding is being done.

Original igntion coils,sparkplug wires & sparkplug caps? Even when new, the coils were marginal, add years of cooking under the tank, and your coils may be breaking down when hot. The sparkplug caps contain a 5000 ohm,non replaceable resistor, that can go bad from age,heat, and vibration.

New coils,sparkplug wires & sparkplug caps are available at www.z1enterprises.com , the 3 ohm,Dyna green coils are a popular replacement.

1-4 are on one coil, and 2-3 on the other. You sure you just don't have the wires on wrong?

MFolks wrote: Original igntion coils,sparkplug wires & sparkplug caps? Even when new, the coils were marginal, add years of cooking under the tank, and your coils may be breaking down when hot. The sparkplug caps contain a 5000 ohm,non replaceable resistor, that can go bad from age,heat, and vibration.

New coils,sparkplug wires & sparkplug caps are available at www.z1enterprises.com , the 3 ohm,Dyna green coils are a popular replacement.

Thanks.
New caps, new plugs, probably original wires since theyre numbered.
BTW, this happens hot or cold but could possibly be worse when hot. Hard to say as its so crazy.

And yeah, checking the firing on 1 and 4 just would have been checking one coil I suppose. I wasnt thinking I guess.
So in the morning Ill see if its actually happening on 2 and 3 as well. If not, I guess that narrows it down to possibly the right coil. Maybe the ignitor?

Will update after I check that.

Thanks a lot for the input.

BTW, where can I locate the auto advancer on the engine?

The timing advancer is located behind the right side engine cover. You might need a new gasket - the old one may tear.

In regards to the coils, a test you can try is to ride the bike at high speed, then stop & feel the coils to see if they are getting hot - press hard w your fingers. I'm assuming you can reach under the tank without getting burned. Mine were getting real hot so I replaced them -->> high speed miss solved.

In the mean time, redo the spark plug wire connections at the coils if you haven't done that already.

Ok Ive found that it definitely gets worse as the bike gets warm.
According to my timing light both coils are missing.
I got the bike hot and tested the coils and all resistance is within spec.

I then tested the resistance over the pickup coils its was very near to the limit (524ish). So I decided to heat them up a bit for maybe 2 minutes with the hair dryer. The spec is 360-540 OHMS, by the way. After that heating one of them got to 543 and the other right at 539. I assume they would get hotter on a summer day ride for sure.


Does this sound like the pickup coils are dying?

Im not sure what else I can test or where to go. Any ideas or suggestions would be awesome about now.

While that is definitely possible, other things have a higher probability of being the problem.

Have you put a voltmeter on the coils' positive connection while running? How about on the igniter's positive and negative while running?