Help me read this plug guys

I thought I might be way rich as I am on stock jetting, but check these pics out, looks ok to me.

Conditions, 70ish degrees

Alt. 400 ft ASL

Pipe, FMF Fatty/Turbine Cor 2

Bike 01 CR250R with around 12ish hrs.


This was with a used but clean plug, warmed up, run up and down the street, full throttle through the gears and kill button at the top and coasted home.


I was going to go down one size in both the main and pilot and change to an S7 nozzle. Should I just leave it? TMX carb by the way, never been touched



Looks like you.may be a little rich but it appears to have good spark with the way it is white at the tip I could be wrong but ive also heard that honda produced their bikes with jets that run rich stock. Im probably wrong but just my two cents, its all just a giant learning experience though right??? :)

Never did a throttle chop, but I thought you read the base of the insulator and looked for a golden brown ring. I can't see the base from that angle.

Are you running 100LL?  I run 100LL and the fuel turns the plug grey instead brown, yours looks grey to me

When setting my main I just keep increasing the main, with each increase I run it WOT for about four seconds till it stumbles, then I just back down one size. It’s easy and works for me. I find this way best to keep plenty of grunt on top and it doesn’t fall on its face

Lean on the main, and needle.  Assuming you did a full throttle chop.  Dark grey, not sludge black if you want it to last.

Looks lean to me

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