TOPIC:

I just 'Winterized' my bike. I found ceramics on 1 + 2 plugs darkened and slightly sooted. I found ceramics on 3 + 4 plugs to be fine (slightly tanned). What's going on here?

Except for a 'hard-wire-coil-mod' & using NGK BR7EIX Iridium plugs in place of the OEM NGK B7ES - the bike is stock and has been running great - Starting 1rst crank & running smooth and strong.

What do the 1 + 2 cylinders have in common that would cause both plugs to show 'rich' indications. I know it's not spark since the coils go 1 + 3 (and) 2 + 4 respectively. It's not exhaust related since they also go 1 + 3 (and) 2 + 4 out to the mufflers.

I'm looking for something common to both the 1 + 2 cylinders. Could it be a cylinder head gasket leak between the 1 + 2 cylinders? (or) Cylinder head nuts (12ea) & bolts (2ea) improperly torqued? I have not done a compression test since I don't have the equipment needed. A simple finger test felt the same on all cylinders.

Here's a picture of the plugs.

Post edited by: BeeGee, at: 2005/10/30 18:51

First, your coils spark 1&4 and 2&3... second, you failed to mention what type air filter you are using. If you are using pods and 1&2 pods are dirty, this would cause the sooty plugs. Also, if the plugs are sooting up, and carburetion was the cause, you can't really say which range of operation is the cause... Most of the time, it is the idle circuit that is the problem and adjusting the mixture screws will solve it... If it is a problem across all ranges of operation, have you adjusted the fuel level in your carb bowls? If so, how was it done?

PS: Since this thread is drifting towards carburetion, I move the thread to the carbs forum.

Post edited by: wiredgeorge, at: 2005/10/31 09:01

If you choose to use precious metal spark plugs, be sure to choose plugs that have the precious metal applied to both the center electrode and ground electrode, i.e. double platinum. The ignition system is a waste spark type (two spark plugs per coil) and the two spark plugs connected to a coil will fire with opposite polarity.

You said the bike is running great. An experiment that wouldn't require messing with the carbs would be to change the spark plugs to the next hotter heat range. This would be B6ES.

Ron

Ron, I understand our bikes are waste spark type ignitions but don't follow your comments regarding the spark plugs (not familiar with this type). Can you amplify please? Also, would it not be a good idea before swapping to a hotter plug of this type to try a non-precious metal plug first to see if this resolved the sooting problem? If he went to a hotter plug using the same type, wouldn't the "wrong polarity firing" issue still be present. Thanks!

Plugs 3 and 4 may be lean due to an air leak.
Plugs 1 and 2 may be dirty due to a dirty filter or just set rich.

Spock

In a waste spark configuration, where one coil fires a pair of spark plugs simultaneously, the spark will leap from the center electrode on one plug and the spark will leap from the side post on the other plug. A double platinum is designed to reduce the voltage required to spark from the side post as well as from the center electrode.

If the owner had sooting with the OEM B7ES spark plugs prior to installing the Iridiums, then my suggestion would be to try a set of B6ES.

Ron

I see that I am a visitor in my previous post. Why did I get logged out while typing my reply?

Ron

Ron G wrote:

I see that I am a visitor in my previous post. Why did I get logged out while typing my reply?

Ron

Because if you are logged on for more than a limited time whithout posting anything, the site will logg you of when you do.


I noticed that the plugs are the resistor type plugs, BR, could that be the problem? Or should this bike have them?

Sooo right! 1+4 2+3 ... I knew that! Not much else though!! With your help here and a service manual in hand I am learning though.
1 -- A clean Stock OEM Air Filter is what's in the bike. Exhaust is also stock OEM. Except for the Wire Mod and the NGK Iridium BR7EIX plugs (NGK's iridium equivalent to the stock NGK B7ES), everything on the bike is stock OEM as it came from the factory.
2 -- Carbs, cleaning/rebuilding, fuel bowl levels etc. all done this Spring by a 'reputable' vintage bike mechanic.

Question:
1 -- wiredgeorge - When you say "Most of the time, it is the Idle Circuit that is the problem and adjusting the mixture screws will solve it" - Are the mixture screws you mention Part #42 in the carb diagram below? The parts list from Kawasaki calls this either "pilot adjusting screw" (or) "air adjusting screw". Which way do I turn the screw to on each carb to make for a leaner condition? How much do I turn it for an initial adjustment?

Question:
2 -- Ron G - If I went to a hotter plug (NGK B6ES) on all 4 cylinders it would be effecting all cylinders and my problem seems to be only 1 + 2. Are you suggesting that I go with a hotter plug in the 1 + 2 cylinders only?

PS. I was having a problem with sooting on all four plugs this Spring. Finding less than 9 volts to the coils I did the hard wire mod. I've been checking plug #4 since and have seen no sooting as you can see from the picture (3 + 4 may even be a little on the lean side). I thought my worries were over. Little did I know 1 + 2 have been sooting since the mod without me being aware. That's where I am right now. As I said the bike has been starting & running 'Great'. Also, I have not been letting it sit idling for lengthy sessions. Only enough to warm it up and settle down the idle / choke issues inherent with KZs before hitting pavement.

I can't load the carb diagram for viewing part #42 on this forum. The file is in the wrong format. The mixture screw I believe you mean wiredgeorge is on the top portion of the carb w/o-ring & spring and is accessible from the carb's exterior.

Post edited by: BeeGee, at: 2005/10/31 19:44

BeeGee wrote:

Sooo right! 1+4 2+3 ... I knew that! Not much else though!! With your help here and a service manual in hand I am learning though.
1 -- A clean Stock OEM Air Filter is what's in the bike. Exhaust is also stock OEM. Except for the Wire Mod and the NGK Iridium BR7EIX plugs (NGK's iridium equivalent to the stock NGK B7ES

That's right, they are. But they are still the resistor type spark plugs:

www.ngksparkplugs.com/techinfo/spark_plugs/partnumberkey.pdf

While the B7ES have no buildt in resistor.

Post edited by: ibsen22000, at: 2005/10/31 19:35