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Is this running too hot or what? It's got about 40 miles on the plugs, this is what they look like the next morning after a 25 mile hill-climbing excursion. Power output is what I would expect from a 92 Polaris 500 efi. Oil brand is unknown (still on previous owner's oil) but the oiler is set rich. This is definitely the lightest color spark plug I've ever pulled out of a sled but normally I intentionally jet on the rich side so I don't know what "correct" really looks like. These are BR9ES. Any comments from the more experienced tuners? Should I be concerned?
 

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journeyman sled/motorhead
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mine are much lighter than that. :p
 

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Thanks :) I was hoping someone would reply before tomorrow morning's ride. Obviously I've seen a lot worse in photos, but if you google "spark plug color" the stuff that comes up, well, none of it looks like what I've got there. Probably the low miles on the plugs plays a part in that. I'm thinking that what we're seeing here is a pretty decent plug color, at least not too lean. I welcome any comments, especially if anyone disagrees with this conclusion. Maybe I'll try to check the piston wash as well, my main concern is that I'm not obviously too lean.
 

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Maybe just a little rich?..... mine are quite a bit lighter than that too. Be careful fiddling with your oil pump arm if you decide to do that.... :!:
 

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almost their, see the tip of the bridge or where ever that thing is called, see that brownish colour, well thats a good place to be
 

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journeyman sled/motorhead
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how did you run the engine right before you pulled the plugs? idle or wfo? I check plugs after a wide open blast with no idle time.
 

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Yup, a little rich for my tastes. I let the porcelen go drk brown, not black. The color change on the ground should be at about the bend. Where iy is now says to rich. Maybe 1 jet size, nothing drasitc though
 

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All the infio here is good, But always take into consideration the temp you are riding in.
Say your jetting is good for -20 and your riding in 30 degrees yes your plugs are going to look rich.
Jetting is always a compromise.
 

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mine are alot lighter too. the skoal man had a a pretty good point. the burn line is halfway up the side electrode. the lower the burn line towards the threads, the leaner. plug colour can be the result of a few things some of which relates to the fuel and oil being used.. the burn line along with piston wash is really what to look for.
 
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