Figured I would start here in touring with this

I had stopped at the dealer a few weeks ago and picked up plugs and they suggested HD Triple Platiniums so I grabbed them - Last night I went to pull the stock ones but before I did I checked the service manual for my 05 EG CLASSIC and it states very clear in there that the correct plugs are "612r" - That these were the stock plugs and to use nothing else. I figured I would pull the stock ones and when I did there were Triple Plat's in there already. Not only that but whoever gapped them must have used a hammer because they were no where near spec (38-43 gap), more like 36 - I didn't like the way they looked and as the front was quite different from thr rear - The front was black and fairly well covered (looking like I was running rich) and the back looked perfect, nice dry lite white ash on it - So I gapped the the triple plat's correctly and put them in (Torque wrench of course!) The kicker is that I rode to work this morning and the bike felt so much better - lot less popping.

What kind of plugs came stock in yours?
What kind do you use now?

Bill (TCSTD) told me that Triple Plat's cause code error in Delphi Systems plus 15 bucks for a pair of plugs is ugly!

 

One thing even more important about your plugs is to "Index" them. Put them in the head so the open side of the plug faces the combustion chamber. You can do this by putting a line on the white top part of the plug that matches the location of the electrode that covers the post. Insert the plug so that the line is between the head bolts. This insures the open side of the plug electrode faces the combustion chamber. You may need a new gasket to make this work.

John

[IMG]local://upfiles/6262/7302AF5568B24709B285B175F9995550.jpg[/IMG]

 

I use the standard HD plugs in my RK. This has been kicked around here on the Forum before and generally the extra money for the plats isn't worth it for the difference in performance. Basically none. Same with indexing your plugs. Unless your ride is capable of generating huge HP/TQ numbers it won't help.

 

Narrow up the gap a few thousands and your bike will run better. Why? Because I researched it and I said so....

 

Advances the spark a bit? (Narrow gap)

 

Btw, I replaced my OEM plugs yesterday as part of my once a year thing - no matter what the mileage. The OEM's had some rust and other nasty oxidation on their bases. No matter what mileage you drive, I'd recommend pulling them after a year and replacing them (mine had 8500 miles on them) along with some anti-seize. I also put a dab of NAPA Sili-Lube on the porcelin - makes the boot slide on and off easier (NAPA sells a tube of SiliLube pretty cheaply - won't melt until around 600 deg F - good for caliper pins too).

 

Original purpose for indexing plugs goes back to very tall dome pistons in race engines, you had to keep the electrode turned away from the piston dome so it wouldn't get knocked shut. Things fit pretty close in there. The thought also was that it would help promote flame travel up over the dome for a more complete combustion.

Most engines today (car and bike) have lower dome or flat top pistons and use a smaller combustion chamber to make compression. Indexing doesn't hurt anything, it's just not really necessary. Not sure if there would be any measurable gain in a v-twin.

But, my bike seems to run better after a wash and an oil change, how about yours? So if you want to index, go for it.