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Plug Question

852 Views 5 Replies 4 Participants Last post by  hotshotfxdl
I just pulled my plugs out for something to do and found the front cyl plug to be
very black. The rear cyl seems to be in great shape a little brown but the
insulator is white and looks normal.I'm running stock plugs they have 3000mi.
Stage one efi with se race slipons and dealer installed download. Any tips on
why the front cyl is so different from the rear. Can you run a hotter plug in the front than the rear ? any help for this problem... thanks
1 - 6 of 6 Posts
I personally run NGK's in my bikes. Below is good info all about plugs

http://www.nightrider.com/biketech/readplugs.htm
dyno/afr

classicglide said:
I just pulled my plugs out for something to do and found the front cyl plug to be
very black. The rear cyl seems to be in great shape a little brown but the
insulator is white and looks normal.I'm running stock plugs they have 3000mi.
Stage one efi with se race slipons and dealer installed download. Any tips on
why the front cyl is so different from the rear. Can you run a hotter plug in the front than the rear ? any help for this problem... thanks
The front cyclinder runs a little cooler,therefore it may run a bit richer.Also that read,is it after idling,did you run under load at a speific rpm and kill the engine etc.does it run well,good gas mileage?YOu shouldn't need to run different heat ranges unless something is wrong.
What conditions was the bike last run under. If it was idle I wouldnt give it much thought. If I want to do a plug read with the bike a normal operating temp I usually ride at a consistant rpm for a 1/4 mile or so and pull in the clutch and shut it off and coast to a stop. Then read the plugs.
For the record I run Denso plugs IXU22
The bikes been stored for a bit and just idled so I guess I should wait 3 months
till the snow melts and look then. god I hate winter
I hear ya !!!! You got a longer wait then me hang in there
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