Timing blur

The timing is set on my kz650 and it runs pretty well but there are two things about the process that bother me.

#1 - using a timing light the F mark for the left side points (1&4) is dead on. But the other has a blur - under the timing light it looks like I'm getting a couple of F marks that alternate and that I can get to hover around the timing mark but won't combine to form one clean F mark.

#2 - Using a test light at first just for S&G I couldn't get a consistent response from either set of points. I assume that the light is supposed to come on when the points begin to seperate and then turn off again? The light would just stay on or start out lit regardless of where the points were in the cycle. I was grounding to the engine and using the spring as a touch point for the light. Response was the same for a light with its own power and for one that hooked up to the battery.

I'm running points with one set of adjustment versus the kind with additional plates on top of the back plate.

Ideas?

Are points contacts perfectly clean, smooth, un-pitted, and correctly gapped (especially on right-hand set of points), all before ignition timing is viewed with the strobe-type timing light?

Perhaps right-side condenser (capacitor) is defective.

Good Luck!

Yeah, I did all that though I was having difficulty having the right gap and keeping the timing marks in view as the points themselves don't move much just the back plate. I would've had to turn the plate really far one way and use up all the space that the slots provide - didn't seem right. I've got a bead on the other kind of points that have additional adjustment capacity.

Condensers only have 3k on them, but its still something to think about

Not sure how your test light was connected, but when one set of points open, the other set closes. There is a feedback loop through the coils such that the circuit is never completely seperated from ground. (Unless you have slightly less than 180 degree dwell by chance.)

To check points on a 4-cyl KZ using a test light or ohmeter/voltmeter, you can avoid confusion by sliding a piece of paper between the points you are not testing. That will then isolate the circuit. You can accomplish the same thing by disconnecting any one of the primary wires (the small wires) on the coils.

You may want to try to isolate the problem somewhat so you can get closer to the cause. Here’s an approach that should indicate whether or not the problem is downstream from the points. By that, I mean it will show if the problems lies within any of the wiring to the coils, the spark plug wires, the spark plugs, or the coils themselves. If you switch the wires coming off the points so the 1&4 points wire is now on the 2&3 points and vice versa AND switch the spark plug caps so the 1&4 caps are now on the 2&3 plugs and vice versa you will have effectively swapped all electrical component between the points and the cylinders. If the “blur” problem moves to the right (2&3) set of points the problem is caused by something listed above (coils, wiring, plugs, etc.) and that’s where you should focus your attention. If, however the problem remains on the left (1&4) set of points you can rule out all the stuff listed above and start looking at the timing advance springs, etc.

Good thoughts!

loud - I'm going to give it whirl (put a card between points). I used two different lights, both grounded to an engine fin with a clamp and the "smart" point in contact with the point spring. Would it be normal/acceptable to be working with less than 180 degrees dwell?

650ed - I feel a little foolish that i didn't think of that myself. If the problem doesn't move by swapping wires what am I looking at? Out of sync carbs? Wouldn't it have to be fuel/air related?

If it doesn't move there could be several causes. I don't pretend to know them all, but I would take a good look at the 1-4 points and the foot that rides on the little points cam. I suppose the carbs or valve clearances could cause the engine to slightly studder when 1 or 4 is firing thus producing the symptoms you describe, but I don't know for sure if that's a possibility. Hopefully a KZRider member with more background on this will join this discussion and share their experiences. Ed