carbon fouled plugs

last night i took my bike out. it ran like crap so i went and picked up some new plugs. i gapped them at .040 like kawasaki told me and it still ran like crap. i only ran it for about 5 minutes on the new plugs. i looked at the manual last night and it says to gap between .028 and .032. so this morning i pulled the plugs to re-gap them. cylinder 1 plug was all dry black carbon, cylinder 2 plug was black carbon but not as bad as cylinder 1. i then pulled plug from cylinder 4 and it still was nice and new looking, no carbon at all on plug. i pulled cylinder 3 plug and its black carbon just as bad as cylinder 1. i now gapped all plugs at .030. do you think the carbon was caused but the un-proper gapped plugs of is it the carbs? if its the carbs, will it need just fuel/air mixture adjustment or will they need to be sync together?

gengomerpyle wrote: last night i took my bike out. it ran like crap so i went and picked up some new plugs. i gapped them at .040 like kawasaki told me and it still ran like crap. i only ran it for about 5 minutes on the new plugs. i looked at the manual last night and it says to gap between .028 and .032. so this morning i pulled the plugs to re-gap them. cylinder 1 plug was all dry black carbon, cylinder 2 plug was black carbon but not as bad as cylinder 1. i then pulled plug from cylinder 4 and it still was nice and new looking, no carbon at all on plug. i pulled cylinder 3 plug and its black carbon just as bad as cylinder 1. i now gapped all plugs at .030. do you think the carbon was caused but the un-proper gapped plugs of is it the carbs? if its the carbs, will it need just fuel/air mixture adjustment or will they need to be sync together?

If not aleady done, would ---

Perform compression test;

Assure valve clearances are within specs;

Visually observe for fat blue spark with plugs removed;

Assure timing advancer isn't sticking (lube pivot points; and if needed, remove, clean and lube);

Perform the clear tube test to assure fuel levels are within specs;

Install four brand new NGKB8ES (or as otherwise specified by FSM) spark plugs.

Good Fortune!

ok ill have to check them. i have BR8ES in the bike now. is it ok to have resistor plugs?

Patton wrote:

gengomerpyle wrote: last night i took my bike out. it ran like crap so i went and picked up some new plugs. i gapped them at .040 like kawasaki told me and it still ran like crap. i only ran it for about 5 minutes on the new plugs. i looked at the manual last night and it says to gap between .028 and .032. so this morning i pulled the plugs to re-gap them. cylinder 1 plug was all dry black carbon, cylinder 2 plug was black carbon but not as bad as cylinder 1. i then pulled plug from cylinder 4 and it still was nice and new looking, no carbon at all on plug. i pulled cylinder 3 plug and its black carbon just as bad as cylinder 1. i now gapped all plugs at .030. do you think the carbon was caused but the un-proper gapped plugs of is it the carbs? if its the carbs, will it need just fuel/air mixture adjustment or will they need to be sync together?

If not aleady done, would ---

Perform compression test;

Assure valve clearances are within specs;

Visually observe for fat blue spark with plugs removed;

Assure timing advancer isn't sticking (lube pivot points; and if needed, remove, clean and lube);

Perform the clear tube test to assure fuel levels are within specs;

Install four brand new NGKB8ES (or as otherwise specified by FSM) spark plugs.

Good Fortune!

gengomerpyle wrote: ok ill have to check them. i have BR8ES in the bike now. is it ok to have resistor plugs?....

As to resistance in the so-called secondary loop, the possibilities include:

"R" spark plugs, such as BR8ES;

Suppression core plug wires (as opposed to solid wire core);

Resistor plug boots/caps.

More than one of these usually furnishes too much resistance.

The basic reason for having any resistance is to help avoid producing "radio noise" interference being picked up from the ignition.

I enjoy excellent ignition performance using Dyna solid core plug wires (that come with non-resistor caps already installed) and non-resistor NGKB8ES spark plugs.

Some of the newer audio listening devices are reportedly better shielded from external noise interference.

If the cage guy's zillion decibel boom-box gets all flukey while sitting next to me at a red light, it doesn't give me heart burn.

Good Fortune!

right now im running stock ignition but i plan on upgrading to dyna s ignition down the road. i have a set of dyna green coils sitting here that someday ill put on the bike. im used to having hondas and having a kawasaki is a different ball game to me. it seems like to do any repairs you pretty much have to take it all apart just to adjust the valves. i think it intimidates me to some degree when it comes to repairing it.

Patton wrote:

gengomerpyle wrote: ok ill have to check them. i have BR8ES in the bike now. is it ok to have resistor plugs?....

As to resistance in the so-called secondary loop, the possibilities include:

"R" spark plugs, such as BR8ES;

Suppression core plug wires (as opposed to solid wire core);

Resistor plug boots/caps.

More than one of these usually furnishes too much resistance.

The basic reason for having any resistance is to help avoid picking up "radio noise" interference from the ignition.

I enjoy excellent ignition performance using Dyna solid core plug wires (that come with nor-resistor caps already installed) and non-resistor NGKB8ES spark plugs.

Some of the newer audio listening devices are reportedly better shielded from external noise interference.

If the cage guy's zillion decibel boom-box gets all flukey while sitting next to me at a red light, it doesn't give me heart burn.

Good Fortune!

well i just went out and started it up for the first time since i re-gap the plugs since i didnt want to wake up all my neighbors and it fired right up (started easier then it has done in a long time) and its running smooth. maybe the correct gap helped but i still need to find out whats causing the fouling of the plugs. ill run the bike tonight and plug the plugs tomorrow and see if its still showing carbon on the plugs.

i will go over to the auto parts store and pick up 4 new B8ES plugs. thanks Patton for you advice. this is why i like this forum, always get good advice and help from the members

Would also measure voltage being actually received at the coil primary terminal, which is supposed to be the same as voltage measured across the battery posts.

Inadequate voltage at the coil, due to loss of voltage somewhere along the line from battery to coil, may result in weak spark at the plugs.



Good Fortune!

Would also assure clean and clear air filter(s).

Air intake might be partially obstructed by something stored underneath the seat, such a gloves or a shop rag.

Oil-type filter(s) might be dirty or over-oiled.

Good Fortune!

i have the factory airbox with a K&N filter (well i think it is anyways, looks like one) and its hard to tell if its dirty but i does spell like gas but i guess that is a normal smell since its hooked to the carbs . i just did an oil change with a new kawasaki filter a couple of weeks ago and may only have 20 miles on it since then. i put 4qts of oil in so i know its a little over full and the oil light started blinking as sone as i did the oil change. someone said i might need to burp the filter, which i have now idea how thats done. it did stop flashing when i rode it about a mile, but since its been sitting for the past to weeks the light is blinking again. the light never flashed before when i did my oil change but in the past, from prior owner the had the spring and washer on top of filter and not on the bottom. i had bought a new spring and washer from kawi to replace it because the spring was bent.

Patton wrote: Would also assure clean and clear air filter(s).

Air intake might be partially obstructed by something stored underneath the seat, such a gloves or a shop rag.

Oil-type filter(s) might be dirty or over-oiled.

Good Fortune!

PATTON, i was thinking, the last time i filled up i went to non-ethanol gas. do you think that may be causing my problem?

gengomerpyle wrote: ...the last time i filled up i went to non-ethanol gas. do you think that may be causing my problem?

I don't think the type of gasoline is causing the blackened spark plugs or the failure of combustion in a particular cylinder.

Good combustion requires these things:
Fuel (correct air-fuel mixture);
Compression (acceptable compression, accompanied by valve clearances within specs);
Spark (fat-blue spark, and properly timed).

That's the basis for the earlier suggestions toward addressing those requirements.

"Checking" the valve clearances is easy.
Remove the valve cover, and use feeler gauges to measure gap between cam and bucket when the cam is pointed away from the bucket. Perhaps the clearances are okay. But if not, then it gets more involved when needing to replace the shims, and an FSM is definitely needed for guidance.

Good Fortune!

ok. ill have to order a new gasket before i remove the cover. the other day i was riding it and its runs strong after about 3000 rpm. its just weird that it all of a sudden started doing this. im not looking forward of replacing the shims if they are out of spec. its seems to be a nasty thing to do after hearing others say what you have to do and reading the manual.