ques about plug chop

GoldenMotor.com

blckwlfny1

New Member
Jul 14, 2010
128
1
0
new york
if you've been using the spark plug a little and the motor was running rich (black plug).
... and then you re-jetted, soaked the plug overnight in carb cleaner and laquer thinner, would you still be able to get an accurate reading or will the black color that is baked on to the plug forever mask any other reading?
Thanks dance1
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
If you can clean the white inner part no problem, but even as long as it is dry you can tell.
You do know that gas richness is not the only factor that will foul a plug right?
Temp range of the plug is a factor too.
Search for the 'Best Spark Plug' topic for more and you may want to just toss that stock kit plug in the trash ;-}
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
some carb cleaner and a wire brush is a good way to clean the plug, and as kCvale said, make sure you are using the correct plug and a good quality one.

I tune all my engines to run a light chocolate brown color plug, the type of oil you use and the amount in the mix will also have an efect on the plug color, main thing is you dont want an engine running in a way that is so lean that you end up with a white or very light gray color plug.

If you're running Opti2 or another high grade synthetic oil at 100:1 ratio, then a medium to dark gray to light brown may be expected, but running conventional oil the plug color should be brown in my experience.

map
 
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blckwlfny1

New Member
Jul 14, 2010
128
1
0
new york
im running a DeNardis motor, boyesen reeds, and an iridium spark plug
fuel mix is at the recommended 40:1 with Yamaha 2-stroke oil
ive idle jetted down 5-sizes and its still black
how can I tell the difference from excess oil in the fuel ratio, or a cold plug, or a rich carb?
...motor wont start without choke but starts right up with it
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Sorry not familiar with what you have so any advice I give now would just be guessing on my part, hopefully someone with more experience with what you hqve will chime in and help.
Map