I have a new 05 FXDWGI, and I know it is super lean from the factory, and it is going to the dealer next week for K&N drop-in, 16 Gauge Double Barrel exhaust, and ECM flash.

This is fairly conservative I know, but I think a good starting point to perk things up while staying away from getting on the rich side.

Now, I pulled the plugs (400 miles) and the porcelin is pure white and the tip looks like it has been in the Sahara, and not a hint of oil / fuel smell.

Question is, I noticed the stock plugs go very deep into the combustion chamber. Is this for emissions purposes? The gap is at 38, in the correct range, but on the tight side.

With the upgrades I will have done is there a different plug suggested and should the gap be opened up a little? It just seems the stock plugs have a tight gap and are set way down in the combustion chamber to help with emissions.

 

I have the same basic upgrades on my EG Classic FI, and I am using the original factory plugs. After the reflash you should seen it richen up a bit and the plugs not be so white.

Regards,

Bill

 

The stock plugs are on the hot side from the factory, you usually will not get much if any color on them except for fuel additives that turn them a bit red. The gap should be between .038-.042. You can also drop down one heat range to a colder plug and the motor will be happier, especially true if you get any pinging.

You also mention the K&N drop in. You would do much better with the stage 1 kit over the K&N drop in. It breathes better and you will see a bit more results with the same download.JMHO

 

Thanks for your comments.

I will try the K&N drop in first, as I figure this will help stay away from still being lean vs. the better flowing Stage 1 kit, and I heard the Stage 1 kit tends to drip a little oil. I am not too concerned with missing out on a few HP / TQ., so I will try this first.

Should I ask the dealer about a colder plug, or will they give me an "EPA" designated answer?

 

The dealer probably will not do it for you, better off just picking them up and putting them in. Can't hurt anything doing it either.

 

Is there a specific Harley plug / #, or something in an NGK or Autolite. I am new to bikes, but always liked Autolites or NGK in performance cars.

 

NGK DCPR8E ( NGK equiv. to the HD stockers, but 1 heat range colder ) should do it.

 

I believe the V Rod plugs that HD sells are the same heat range as the NGKDCPR8E (1 heat range colder than the stock big twin plug)
Just double check if you go htis way to be sure.

 

Stock heat range ... Autolite 4164
one range colder ... Autolite 4163

 

Are these plugs the same deep length as the stock HD plugs, and is a gap of 40 about right?