Sparkplugs black and grey

[CBX-Six]

I have two Grey and four Black sparkplugs. Air screws are all in the same position 1 1/2 turns out.
For a try, I installed two iridium plugs to seeif it gave any difference in colour, with out better result.
The plugs are DR8ES and have done 3-400 km.
The bike runs fine and draw well from 2000 rpm in 5th gear.
Air filters are K&N and all clean.
Any suggestions why there are different colours on the plugs ?

[daves79x]

I think you said you had individual filters? If so, this is very normal. Each filter will affect it's cylinder a bit differently, due to positioning and the resulting differences in air flow. Your outside filters are greatly affected by crosswinds, and most noticeably, your knees. This is what you have to live with with pod filters. If you want nice clean plugs across the board, go back to the stock intake system.

Dave

[steve murdoch icoa #5322]

I remember Larry Benjamin had his smoothbores with K&N pods jetted differently for the outside cylinders.

[Gearheadgregg]

My findings is with Pods it leans out a already Lean factory setting , i am 2 steps up on Slow jets and and stepped up main to 120 and have a Dyna Jet needles..i must have a a really strange motor , It still has perfect plugs and has absolutely no midrange issues at all such a joy to ride ,Cold start is very easy also. Oil residue will collect at the bottom of the plug thread like these shown also , Leak down test would be my thoughts not knowing what your motor millage is . Greg

[CBX-Six]

The filters have the same size/tube length on No. 1 & 6 (outer cylinders L & R), No. 2 & 5 same filters/tube length and 3 &4 have one big filter together. The picture off the spark plugs seen from the front are from left side No. 1, 2, 3, 4, 5 & 6 as de-mounted from the engine. In my humble opinion No. 1 & 6 should have the same color, as well as No. 2 & 5. The colors are the same every time I check the spark plugs, so I don`t think knees and side wind is a issue. I will get the carbs cleaned with new gaskets and synchronized in the coming months and see if that could make a difference. Could also have something to do with oil consumption and weak piston oil rings. Km is 89000.