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I have a 2002 Roadking Classic with EFI,, and 3500 miles on the bike,, i pulled the sparkplugs to see how there burning,, and the frount plug is all black,, and the back plug is tan ??? is this a problem ???
 

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Black at 3500 miles? I would say yea something is up. I am going to assume you mean the plug is carbon fouled? Seems to early for a sticking injector but one never knows.

Your air/ fuel mix is rich. How is the ignition?

In that it is an 02, take it in under warranty. Don't ask the dealer if there is a problem, TELL him there is a problem and you want it fixed.
 

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Generally non oily black plug= rich, tan/white plug = lean.
The front cylinder is the power stroke cylinder in that most of the power comes from the front. In the Delphi EFI, the front cylinder gets 1-4% more fuel at any given RPM and throttle position. At idle (0% TP) 1000RPM, the front gets about 10% more fuel. At WOT it gets 1-1.5% more.
When I tuned up my FLHTCUI 1550 I increased the amount of fuel to the front proportional to the rear because I found significant knock retard going on in the front using the factory SE calibration.
So guarenteed that front cylinder is burning a richer mixture and more fuel and all other things being OK, it will show darker than the rear.
I rotate my plugs front to back every 500mi. (and reindex)
 

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If you've been spending a lot of time in traffic or idling, that might explain the black plug. I don't think it's normal based on what I've seen. As someone else said, if it's still under warranty, let the dealer check it out or get it on a dyno somewhere.

I don't agree with Tsuter on his take on reading plugs. Just my opinion. Given todays gasolines and all the additivies, it is awful hard to read plugs unless they are on the extreme end of rich or lean. A plug that is off white to tan is considered right on by almost every mechanic I've talked to. Lean plugs are usually blistered and real noticable. Rich are obviously black.
 

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tsuter, when you index your plugs is the electrode pointed straight across to the opposite side of the cylinder head?
Where did you get the washers? I could only find 14mm washers but my plugs are 12mm.
 

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tsuter said:
The front cylinder is the power stroke cylinder in that most of the power comes from the front. In the Delphi EFI, the front cylinder gets 1-4% more fuel at any given RPM and throttle position. At idle (0% TP) 1000RPM, the front gets about 10% more fuel. At WOT it gets 1-1.5% more.
Hmmm, I always thought you wanted to go as lean as possible without detonating to make the most power.
 

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With stock heads and flat top pistonst the gap would point at 1-2:OO o'clock on the front and 10-11:00 on the rear or basically towards the intake - but you'll get a lot of debate on this. With performance heads and high compression pistons it will be specific to the compression chamber. Usually you got about 1/4 of a turn of room in the plug washer when you tighten it. If they don't line up switch front to rear and try again. A second squishy washer will give you plenty of room. You can get brass indexing washers from Performance Products part#802062 but I'm not sure the size.
Do not do this if you have bevel seated washerless plugs for any reason on any motor.
There was another post on this so just to be clear - you won't see these type of adjustments on a dyno .....but...... do ten things like this at a half of a percent each and it adds up.
 

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quote:
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Hmmm, I always thought you wanted to go as lean as possible without detonating to make the most power.

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Speaking strictly AF ratios - not CRs, power comes from an AF ratio of 12.8/1 and lower for the same CR. That means more fuel and the engine runs cooler. But to get the power you must get complete combustion. Ratios of 12.8 to 14 are fine for cruising and light loads and great if you're the EPA but not for power and the engine runs hotter. Run em rich, then advance your factory ignition into it until you get spark retard, then back the ignition slightly. Each cylinder is optimized separately. Warning, dinking with the ignition is not for the faint of heart.I'll try and post a before (EPA) and after(EPA) picture of the SE 1550 Stage I calibration if I can figure out how to post pictures.
 

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I suppose it depends a lot on what fuel you are running.

I can guarantee that if you run the oxygenated fuels we are stuck with in the southwest and most of CA, if the spark plugs show any color you are running too rich. They look chalk white.

On the TC with the bath tub chamber you index the plugs like TS said gap towards the intake, on an EVO you would point the gap towards the squish zone ie the flat side of the "D".
 

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One thing that can cause the impression of these bikes running rich is a lot of short trips in cold weather as you are basically running the bike on the choke all the time.
Under this type of service the fuel mileage on the EFI bikes goes to $hit, much more so then on a carb bike operated properly.
 

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I wouldn't worry about indexing spark plugs
A quality spark plug would be of more benefit
(especially if you still have the HD plugs!!)
 

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So, just how do you get the gap in the right position?
one twist of the wrench too much, and..... :confused:

I have heard doing this right will give you a horse or two.
 

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To index the plugs, mark the gap side of the ceramic with a black marker. Align the black mark (gap side of electrode) so the gap faces into the "squish'.
 

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Harleyhog,

Tsuter is correct. just so you know, indexing washers usually come in 3 sizes. 043 rotates the plug counterclockwise 105 degrees, .054 rotates the plug counterclockwise 210 degrees, and the .064 rotates the plug counterclockwise 315 degrees. Hope that helps you.

WFO, it just sounds better that way!!
 

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Would you take out the regular squishy washer that comes with the HD or SE plugs? Then use the indexing washers? I'm pretty sure the heads of the CVO 103 are flat and not beveled where the spark plug seats.
By taking the squish washer out, the tip would extend further into the chamber. This might make the plug run hot?
How does everyone do it? I cannot remember how the factory plugs came on the bike.
 
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