Sooty spark plugs.

[suzukizone]

Have come near to resolving the rich running & idle problems of my '81GS850.
One big thing was the PILOT AIR JETs were #180 but bike was spec'd for #190 jets. Runs so much better with this change.
However, the plugs still look rather sooty in the metal "bore"-where the porcelin insulator dwells. The tips are actually pretty close to the right color but always I get this layer of soot on the metal walls. Hope this can be seen in the image
If the bike runs good why is there all the soot there then? I'm really looking at the electrode tips as the major feedback to how the engine is running.
More curiosity now as the old girl is running better than ever & holding idle as she should.
Thanks,

Douglas

[BassCliff]

Hi,

That's a small picture, can't really tell a lot. (But I don't think they look that bad.) Why not get yourself a free account on a picture hosting website and post up full sized pictures? See the article: Posting Pictures To GSR

Here's some spark plug reading info for you:

How To Read Your Spark Plugs
(Everything you ever wanted to know about reading your spark plugs, but were afraid to ask.)

http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp
http://www.dansmc.com/spark_plugs/spark_plugs_catalog.html

More technical/racing articles about plugs:
http://www.4strokes.com/tech/sparkplg.asp
http://www.4secondsflat.com/Spark_plug_reading.html
http://www.dragstuff.com/techarticles/how-to-read-plugs.html


Thank you for your indulgence,

BassCliff

[bobthebiker88]

what I'm seeing is plugs #1 and 3 are lean, #2 looks close to right, and #4 is rich.

[suzukizone]

Sooty spark plugs.

what I'm seeing is plugs #1 and 3 are lean, #2 looks close to right, and #4 is rich.

Don't trust the actual color as I can see the tones look a bit different from the actual plugs. Also my photoshop images look different than how the sent pics look.

My real concern is the layer of black to black/brown soot on the inner wall of the metal plug body. It is out of line with the actual tip color. Why so sooty there when the electrode tips are getting close to normal?

Again, bike is running close to perfect finally, just don't get the look of the plugs.

Will look into figuring out how to post pics to the site mentioned.

Thank you for your replies.
Douglas