Is my bike running lean or rich? Spark plugs pics included!

[vyzr]

Hi guys and gals,

I don't know how to read spark plugs (well, sort of, black is rich and white is lean?).
I'd like to know whether I should lean out or richen my carbs.
Could someone please read my spark plugs for me, or direct me to a nice spark plug reading thread? (I searched, but couldn't find pictures to compare).


Onto the pictures!





(Looks like a crumb on threads of this one, weird.)




Thanks in advance and goodnight!

Cheers,
Brock.

[Outlander]

Look rich to me.

[Nessism]

What kind of bike and how does it run?

Plugs don't look too bad to me, how old are they?

[coltrain]

Hard to gauge plug color through pictures over the internet but what your looking for is a chocolate brown color. It does look to me like your close to that. If it is closer to a whiter/grey color then you need to go richer just a hair.

[KiwiGS]

They don't look to bad to me.

[Joe Nardy]

Vyzr,

Here's a nice pictorial description of plug reads: http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html

The chocolate brown color coltrain refers to is the color of the white insulator in the center of the plug.

Thanks,
Joe

[rapidray]

If you look at the heat those plugs have had in them the bike is LEAN! you want the heat to end right in the MIDDLE of the grounding strap on the plug. Those plugs show the heat line WAY closer to the threads than I would be comfortable with. Are these pictures of it after a high RPM plug chop or just from riding it around? If it IS a plug chop you are probably from 2-3 sizes too small on the mains. If it's from just riding around the needles AND the mains are lean. If there is that little color & that MUCH heat on the strap it is too lean from the midrange on. Good luck, Ray.

[vyzr]

WOW!
You guys are fast.

The bike is a 1983 GS550E, with the Mikuni BSW30SS carbs.
I put the plugs in about 1500km ago.
I took the carbs apart last summer and dipped them, but I forget how many turns I used for the needles and mains. Everything are stock sizes.
Does anyone know the correct amount of turns?

The plugs, as can be seen from the pics, are the NGK Iridium DR9EIX, surprisingly the D9EA were not in stock. Would the Iridium plugs make a difference from the regular ones? If so, I'll order some regular ones.

Also, I've been just riding the bike to and from school with the occasional high RPM surge for fun. I pulled the plugs after normal riding in rush hour traffic coming back from school.

rapidray, when you mention the heat line, are you referring to the darker banding (carbon buildup?) that goes a little bit up the grounding strap from the threads?

And btw, the bike runs great, nothing to complain about except the odd "lack of fuel feeling" sometimes when I give it throttle in colder weather.

Thanks again guys/gals. I'm looking forward to more info coming my way (hopefully :-D).

Thanks for listening.

-Brock.

[Big T]

I'd go back to the stock plugs, you can always put these back in

It looks to me like you're using lots of choke on start up, and that it's running lean

[Schweisshund]

I have an 83 GS 550 E too. Why not do a forum search on synchronizing carbs. You will find a lot of info.

Also, take your choke cables out, spray in deep creep seafoam, get a fishing line and clean out those tiny little holes.

If by chance you need to take your carbs apart, do the same thing with fishing line. You can also saturate your carbs with deep creep seafoam (OUTSIDE) and it will take a while to crank and lots of carbon will be coming out your exhaust.

lather rinse repeat.

[chef1366]

Vyzr,

Here's a nice pictorial description of plug reads: http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html

The chocolate brown color coltrain refers to is the color of the white insulator in the center of the plug.

Thanks,
Joe

Nice link Joe!

[rustybronco]

Can't see them well enough to tell, but their not tightened enough.

http://www.dragstuff.com/techarticles/reading-spark-plugs.html

Other Things To Look For

The round flat circular area of the plug at the end the threads should be dark gray or flat black and should not be sooty. If it is sooty then it can mean that your plug has not been tightened enough and you are sucking and blowing fuel and air past the threads of the plug.

read the page and the links at the bottom also. there is a lot to know about reading plugs.

http://www.thegsresources.com/_forum/showpost.php?p=668262&postcount=8

[flyingace]

Your plugs are not the only determining factor when it comes to leaning or richening the mixture. As you can see from the replies, there is no agreement about these plugs.

Does the bike ping, smoke, hesitate? What kind of gas mileage are you getting? If your bike runs well, why fix something that isn't broken. Is there some reason you believe it needs this adjustment? I wouldn't change anything based on these plug pictures unless these was something else out of whack.

[Calvin Blackmore]

wow a canadian model no less
the kind with no preset idle screws
alas the oem manual only lists the screws as pre-set nd I have no non US supplement.

have there been any mods doen on the carbs or the intake and exhaust?
is it stock I mean to say.

My NGK D9EA plugs look about the same under stop and go driving conditions but go light tan when doing sustained highway driving.

being as your rich and can afford iridium plugs send me four and well compare and contrast the results.