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Spark Plug Colour

propflux01

Active Member
Just got a good 65F day to ride my 06 ultra after installation of upgraded hydraulic tensioner, cam plate and Andrews 21 Conversion cams. Also installed EJK GEN 3 controller. Went out 170 miles. Started with full tank. Filled upon return and put in 4.6 Gallons. Averaged 36MPG. No decel pop, nice power, didn't seem to run hot, no ping.

Got home, drained oil and pulled plugs to check colour.

So: Lean, Rich, or just right?

Front Cyl on left, Rear Cyl on right

 
I would say looks good to me.
If the towel is for the plugs being hot to hold for picture, I would not pull plugs from a hot aluminum head for fear of distorting threads.....:s
 
I like to see a grayish brown color with mine. White too lean, black too rich. I'd also say you're good to go. Bet you love that cam.
 
No, towel is for wife's delicate hands!!

Glad to hear its good. Mileage I wasn't too impressed with, but perhaps coming down on the yellow alittle might help that.
 
No, towel is for wife's delicate hands!!

Glad to hear its good. Mileage I wasn't too impressed with, but perhaps coming down on the yellow alittle might help that.

Remember that the better the bike performs the harder you ride it. So, right wrist application is in proportion to fuel mileage and rear tire wear... Have fun....
 
Plug color looks good. However looking at the pic they appear to be the plugs(old) that t were used prior? I would start with a fresh set for your next test. You have some left color from being old, used, even though you put 170 mi. on them. Just my train of thought.
tourbox
 
Yes, they are the older plugs. I cleaned them when I had them out for the cam change. Replacement is in order then.
 
The plugs look good, I would not reuse them tho, once the crush washer is tightened you could lose heat transfer by reusing them JMO
 
Well somebody is probably going to say I'm just to old school but I will put my .02c in anyway. Here is the way I was taught to read a sparkplug when I was racing motocross. First install new plug(s). Next run the bike up to 50 to 60mph, and hold it steady for 5 to 10 min. Next chop the throttle closed pull in the clutch and turn off ignition and bring the bike to a quick stop. Remove the plugs quickly and read, you're looking for tan and no deposits. I have also read recently from a "wise" member here on the forum, that with the introduction of ethanol it is almost impossible to get a good read on plugs no matter how you do it.
 
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