SPARK PLUG PICS - what do you think

This plug has 10 - 15 minutes riding time. At first I was riding 1/4 to 1/2 throttle, changed pilot jet smaller and adjusted air screw. The last few minutes was in 5th gear at wide open throttle from low rpm's to full rpm's a few times ending with pulling in the clutch and killing the engine.


This plug was after riding 1-1/2 hours (track time). It was a sandy track that started out muddy and got really nice later.


Appreciate any comments on jetting, thanks

That looks pretty good, I was always told to look at the insulator near the bottom for the proper reading. THe black carbon deposits could just be from idling as the bike will be rich at idle, 2 strokes will respond to jetting properly under load.

The tanned color is what you want.

However the experts all say that plug readings mean diddly shit these days with the additives you find in gasoline at every gas station.

Personally I go by how the bike feels, and not just by a plug reading. Spooge really doesn't mean jack either because there are just way too many variables to determine spooge output.

You have a nice plug there, ever so slight rich ring at the bottom, which is about right. generally, if you're going to run WFO in deep sand or other high load conditions, you probably should run as rich as it will tolerate without blubbering, extra cooling and extra oil.

I destroyed a motor with a plug that looked like that on pump 93 gas. If you decide

to keep that jetting I would be very careful in cool weather and sand tracks unless I was running race gas. I would go up a least one maybe two on the main.

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