What we need to check on the spark plug?

[Deleted]

Here the spark plug of my Kymco with a 72cc kit.

To know if i running lean or rich what i need to check first?
(See Picture)
A, B or C???



I ask this question beacause a dealer said to me i running rich, the ring (A) was black!

[90GTVert]

A : Looks pretty good to me. You have dry black deposits, but they don't appear to be thick. That indicates that you are getting plenty of fuel.

B : This is where everyone says to look for a color. I can see some color there, and the fact that your heat range appears to be too hot makes me think it might be OK. The hotter the plug, the cleaner it will keep itself.

C : Looks like your spark plug heat range is a bit hot. You might want to try one heat range cooler of a spark plug.

That said, I rarely have the text book results when trying to tune. I generally still look for a color on the porcelain, although I do pay attention to the other elements to make a decision. The most important thing for me is feeling the way the engine responds and combining that with what I'm seeing on the plug.

[190mech]

I agree with Brent,more seat of the pants tuning,a bit of plug color checks.If we had Cylinder Head Temp and Exhaust Gas Temp gauges,we whould know for sure,but these instruments would cost more than some scooters on this board!!

[2strokd]

Agreed!!!
I go with the "seat of the pants" method.
Takes time learning "the feel" tho....
My head temp gauge helps allot!